Document and Entity Information - shares	6 Months Ended
Document and Entity Information - shares	Jun. 30, 2017	Aug. 10, 2017
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jun. 30, 2017
Document Fiscal Year Focus	2017
Document Fiscal Period Focus	Q2
Trading Symbol	DARE
Entity Registrant Name	Dare Bioscience, Inc.
Entity Central Index Key	0001401914
Current Fiscal Year End Date	--12-31
Entity Filer Category	Smaller Reporting Company
Entity Common Stock, Shares Outstanding		6,047,165

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 7,244	$ 34,950
Accounts receivable, prepaid expenses, and other current assets	890	1,840
Total current assets	8,134	36,790
Property and equipment, net	17	668
Other assets		230
Total assets	8,151	37,688
Current liabilities:
Accounts payable	660	1,446
Accrued expenses	189	4,611
Current portion of loan payable		8,382
Current portion deferred revenue	2,500	2,500
Total current liabilities	3,349	16,939
Long-term liabilities:
Loan payable, net of current portion		4,439
Deferred revenue	743	1,993
Other long-term liabilities		1,206
Total long-term liabilities	743	7,638
Commitments and contingencies
Stockholders’ equity:
Preferred stock $0.01 par value; 5,000,000 shares authorized, no shares issued or outstanding
Common stock, $0.0001 par value; 120,000,000 shares authorized, 2,903,172 and 2,893,718 shares issued and outstanding at June 30, 2017 and December 31, 2016, respectively
Additional paid-in capital	215,213	213,791
Accumulated deficit	(211,154)	(200,680)
Total stockholders’ equity	4,059	13,111
Total liabilities and stockholders’ equity	$ 8,151	$ 37,688

Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares	Jun. 30, 2017	Dec. 31, 2016
Statement Of Financial Position [Abstract]
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.0001	$ 0.0001
Common stock, shares authorized	120,000,000	120,000,000
Common stock, shares issued	2,903,172	2,893,718
Common stock, shares outstanding	2,903,172	2,893,718

Condensed Consolidated Statements of Operations (unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Income Statement [Abstract]
Revenue	$ 642		$ 1,834
Operating expenses:
Research and development	1,292	$ 7,522	5,943	$ 17,292
General and administrative	3,375	2,773	6,962	5,891
Gain on asset sale			(1,500)
Total operating expenses	4,667	10,295	11,405	23,183
Other income (expense):
Interest income	20	25	53	41
Interest expense		(597)	(797)	(1,260)
Other income (expense)	(130)	8	(159)	1
Total other expense, net	(110)	(564)	(903)	(1,218)
Net loss attributable to common stockholders	$ (4,135)	$ (10,859)	$ (10,474)	$ (24,401)
Net loss per share attributable to common stockholders:
Basic and diluted	$ (1.42)	$ (3.97)	$ (3.61)	$ (8.92)
Weighted-average common shares outstanding:
Basic and diluted	2,903,139	2,736,397	2,902,865	2,736,330

Condensed Consolidated Statements of Cash Flows (unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Cash flows from operating activities:
Net loss	$ (10,474)	$ (24,401)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation	1,352	1,457
Noncash rent expense	(153)	134
Depreciation and amortization	80	127
Amortization of debt discount and deferred financing costs	610	242
Loss on disposal of property and equipment	177	4
Deferred revenue	(1,250)
Gain on asset sale	(1,500)
Changes in operating assets and liabilities:
Accounts receivable, prepaid expenses and other current assets	950	(334)
Accounts payable	(785)	(458)
Accrued expenses	(4,423)	(1,272)
Net cash used in operating activities	(15,416)	(24,501)
Cash flows from investing activities:
Purchases of property and equipment		(472)
Decrease in restricted cash	230	117
Proceeds from the sale of assets	1,894
Net cash provided by (used in) investing activities	2,124	(355)
Cash flows from financing activities:
Proceeds from sale of common stock	70	41
Payments on loan payable	(13,077)	(3,900)
Payment of end of term charge on loan payable	(1,407)
Net cash used in financing activities	(14,414)	(3,859)
Net decrease in cash and cash equivalents	(27,706)	(28,715)
Cash and cash equivalents — Beginning of period	34,950	75,908
Cash and cash equivalents — End of period	7,244	47,193
Supplemental cash flow information — Interest paid	$ 269	$ 708

Nature of Business and Operations

6 Months Ended

Jun. 30, 2017

Organization Consolidation And Presentation Of Financial Statements [Abstract]

Nature of Business and Operations

1.	NATURE OF BUSINESS AND OPERATIONS

Nature of Business — On July 19, 2017, Cerulean Pharma Inc., now Daré Bioscience, Inc., a Delaware corporation (“Daré” or the “Company”) completed its purchase of Daré Bioscience Operations, Inc., a Delaware corporation and private company (“Private Daré”), pursuant to the terms of that certain Stock Purchase Agreement, dated March 19, 2017, by and among the Company, Private Daré and the holders of capital stock and securities convertible into capital stock of Private Daré (the “Stock Purchase Agreement”). The stockholders of the Company approved the purchase of Private Daré and the other transactions contemplated by the Stock Purchase Agreement (collectively, the “Stock Purchase Transaction”) on July 19, 2017. Except as described in Note 11, “Subsequent Events,” the accompanying unaudited condensed financial statements do not give effect to the Stock Purchase Transaction. The historical financial statements have been labeled Cerulean Pharma Inc. for the purposes solely of this filing, which was the entity name in effect for the historical periods presented.

Prior to the Stock Purchase Transaction, the Company was an oncology-focused company applying its proprietary Dynamic Tumor Targeting™ Platform, (the “Platform”), to develop differentiated therapies. The Platform is designed to create nanoparticle-drug conjugates (“NDCs”) with the aim of providing safer and more effective therapies for patients living with cancer. NDCs consist of anti-cancer therapeutics covalently linked to a proprietary polymer. On July 19, 2017, the Company completed the sale of the Platform to Novartis Institutes for BioMedical Research, Inc. (“Novartis”) for $6.0 million. Following the Stock Purchase Transaction and sale of the Platform to Novartis, Daré is a healthcare company committed to the development and commercialization of innovative products in women’s reproductive health. Daré’s business strategy is to license the rights to novel reproductive health product candidates, some of which have existing clinical proof-of-concept data, and to take those candidates through advanced stages of clinical development. For more information regarding our business following the Stock Purchase Transaction, please see Part II, Item 5 of this Quarterly Report on Form 10-Q.

Basis of Presentation — The accompanying unaudited condensed consolidated financial statements present the historical results and financial position of Cerulean Pharma Inc. and its subsidiary, Cerulean Pharma Australia Pty Ltd, a wholly-owned Australian-based proprietary limited company, prior to the Stock Purchase Transaction and sale of the Platform to Novartis. These financial statements have been prepared in accordance with accounting principles generally accepted in the United States (“GAAP”) for interim financial reporting and as required by Regulation S-X, Rule 10-01. Accordingly, they do not include all of the information and footnotes required by GAAP for complete financial statements. In the opinion of management, all adjustments (including those which are normal and recurring) considered necessary for a fair presentation of the interim financial information have been included. When preparing financial statements in conformity with GAAP, the Company must make estimates and assumptions that affect the reported amounts of assets, liabilities, revenues, expenses and related disclosures at the date of the financial statements. Actual results could differ from those estimates. Additionally, operating results for the three and six months ended June 30, 2017, reflect the results of operations of the Company prior to the Stock Purchase Transaction and sale of the Platform to Novartis and are therefore not indicative of the results that may be expected for any other interim period or for the fiscal year ending December 31, 2017. For further information, refer to the consolidated financial statements and footnotes included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2016, as filed with the Securities and Exchange Commission (“SEC”) on March 31, 2017, and amended on April 28, 2017 and June 13, 2017 (the “2016 Form 10-K”).

Following the closing of the Stock Purchase Transaction, which included the sale of the Platform to Novartis for $6 million, the Company believes that its existing resources will be sufficient to fund its planned operations for approximately two years.

Reverse Stock Split — on July 20, 2017, the Company effected a 1-for-10 reverse stock split of its outstanding common stock (the “Reverse Stock Split”). The accompanying consolidated financial statements and notes to the consolidated financial statements give retroactive effect to the Reverse Stock Split for all periods presented. The shares of common stock retained a par value of $0.0001 per share. Accordingly, stockholders’ equity reflects the Reverse Stock Split by reclassifying from common stock to additional paid-in capital an amount equal to the par value of the decreased shares resulting from the Reverse Stock Split.

Significant Accounting Policies

6 Months Ended

Jun. 30, 2017

Accounting Policies [Abstract]

Significant Accounting Policies

2.	SIGNIFICANT ACCOUNTING POLICIES

There have been no material changes to the significant accounting policies previously disclosed in the 2016 Form 10-K.

Recent Accounting Pronouncements — In November 2016, the Financial Accounting Standards Board (the “FASB”) issued Accounting Standards Update 2016-18, “Statement of Cash Flows - Restricted Cash (Topic 230)”. This new standard requires companies to include amounts generally described as restricted cash and restricted cash equivalents in cash and cash equivalents when reconciling beginning-of-period and end-of-period total amounts shown on the statement of cash flows. This guidance is effective for annual and interim reporting periods beginning after December 15, 2017, and required retrospective application. The Company is currently evaluating the effect this standard will have on its consolidated financial statements and related disclosures.

In August 2016, the FASB issued Accounting Standards Update 2016-15, “Statement of Cash Flows (Topic 230)” (“ASU 2016-15”). ASU 2016-15 provides guidance to clarify how cash payments for debt prepayment or debt extinguishment costs are to be classified in the statement of cash flows. The standard is effective for financial statements issued for fiscal years beginning after December 15, 2017, and interim periods within those fiscal years. The Company is currently evaluating the effect this standard will have on its consolidated financial statements and related disclosures.

In February 2016, the FASB issued Accounting Standards Update 2016-02, “Leases (Topic 842)” (“ASU 2016-02”), which provides new accounting guidance on leases. ASU 2016-02 requires lessees to recognize leases on their balance sheets, and leaves lessor accounting largely unchanged. The amendments in ASU 2016-02 are effective for fiscal years beginning after December 15, 2018 and interim periods within those fiscal years. Early application is permitted for all entities. ASU 2016-02 requires a modified retrospective approach for all leases existing at, or entered into after, the date of initial application, with an option to elect to use certain transition relief. The Company is currently evaluating the impact of this new standard on its consolidated financial statements and related disclosures.

In May 2014, the FASB issued Accounting Standards Update 2014-09 (ASC 606), “Revenue from Contracts with Customers” (ASU 2015-09), which affects any entity that either enters into contracts with customers to transfer goods and services or enters into contracts for the transfer of nonfinancial assets. In August 2015, the FASB issued Accounting Standards Update 2015-14, “Revenue from Contracts with Customers” which defers the effective date of ASU 2014-09 for all entities by one year. ASU 2014-09, which has been codified with the Accounting Standards Codification as Topic 606, is now effective for public companies for annual reporting periods beginning after December 15, 2017, including interim periods within those reporting periods. ASC 606 outlines a single comprehensive model for entities to use in accounting for revenue arising from contracts with customers and supersedes most current revenue recognition guidance, including industry-specific guidance. In addition, ASC 606 provides guidance on accounting for certain revenue-related costs including, but not limited to, when to capitalize costs associated with obtaining and fulfilling a contract. ASC 606 provides companies with two implementation methods. Companies can choose to apply the standard retrospectively to each prior reporting period presented (full retrospective application) or retrospectively with the cumulative effect of initially applying the standard as an adjustment to the opening balance of retained earnings of the annual reporting period that includes the date of initial application (modified retrospective application). Since ASU 2014-09 was issued, several additional Accounting Standards Updates have been issued and incorporated within ASC 606 to clarify various elements of the guidance. The Company plans to adopt this guidance on January 1, 2018. The Company has not yet determined whether it will utilize the full retrospective or the modified retrospective adoption method and continues to evaluate the impact that adoption will have on its consolidated financial statements.

Net Loss Per Share Attributable to Common Stockholders

6 Months Ended

Jun. 30, 2017

Earnings Per Share [Abstract]

Net Loss Per Share Attributable to Common Stockholders

3.	NET LOSS PER SHARE ATTRIBUTABLE TO COMMON STOCKHOLDERS

The Company computes diluted loss per common share after giving effect to the dilutive effect of stock options, warrants and shares of unvested restricted stock that are outstanding during the period, except where the inclusion of such securities would be antidilutive.

The Company has reported a net loss for all periods presented and, therefore, diluted net loss per common share is the same as basic net loss per common share.

The following potentially dilutive securities that were outstanding prior to the use of the treasury stock method have been excluded from the computation of diluted weighted-average shares outstanding, because the inclusion of such securities would have an antidilutive impact due to the losses reported (in common stock equivalent shares):

	As of June 30,
	2017		2016
Options to purchase common stock		544,110		414,598
Warrants to purchase common stock		30,503		36,556

Property and Equipment

6 Months Ended

Jun. 30, 2017

Property Plant And Equipment [Abstract]

Property and Equipment

PROPERTY AND EQUIPMENT

Property and equipment consists of the following (in thousands):

	As of June 30, 2017			As of December 31, 2016
Laboratory equipment	$	—		$	1,548
Computer equipment		100			371
Office furniture and equipment		—			66
Leasehold improvements		—			75
		100			2,060
Less accumulated depreciation and amortization		(83	)		(1,392	)
Property and equipment, net	$	17		$	668

On March 19, 2017, the Company entered into the Novartis Asset Purchase Agreement under which the Company agreed to sell and assign all of its right, title and interest in and to the patent rights, know-how and third-party license agreements relating to the Platform. The sale of such assets under the Novartis Asset Purchase Agreement, which required the approval of the holders of Cerulean Common Stock, resulted in substantially all of the Company’s lab research activities terminating. As a result, in connection with the execution of the Novartis Asset Purchase Agreement, the Company determined to dispose of all of its lab equipment and initiated a program in March 2017 to locate a buyer and offer such equipment for sale which it completed in early April 2017. On May 31, 2017, the Company entered into a Lease Termination Agreement with its landlord to terminate its lease for office and laboratory space at the former headquarters at 35 Gatehouse Drive in Waltham, Massachusetts. Prior to the termination of its lease, which was effective on May 31, 2017, the Company had disposed of substantially all of the remaining computer equipment, office furniture and equipment, and leasehold improvements. The Company recorded a charge of $177,000 for the disposal of property and equipment which is included in other expense.

Accrued Expenses

6 Months Ended

Jun. 30, 2017

Payables And Accruals [Abstract]

Accrued Expenses

5.	ACCRUED EXPENSES

Accrued expenses consist of the following (in thousands):

	As of June 30, 2017		As of December 31, 2016
Accrued clinical trial costs	$	25	$	2,648
Accrued contract manufacturing expenses		—		226
Accrued compensation and benefits		44		1,080
Accrued interest		—		82
Other accrued expenses		120		575
Total accrued expenses	$	189	$	4,611

Loan Agreements

6 Months Ended

Jun. 30, 2017

Debt Disclosure [Abstract]

Loan Agreements

6.	LOAN AGREEMENTS

On January 8, 2015, the Company entered into a loan and security agreement with Hercules to borrow up to $26.0 million (the “Hercules Loan Agreement”). The proceeds were used to repay the Company’s then-existing term loan facility and for general corporate and working capital purposes. On March 17, 2017, the Company entered into a payoff letter with Hercules pursuant to which the Company agreed to pay off and thereby terminate the Hercules Loan Agreement. Pursuant to the payoff letter, on March 20, 2017, the Company paid a total of $12.4 million to Hercules, representing the principal, accrued and unpaid interest, fees, costs and expenses outstanding under the Hercules Loan Agreement in repayment of its outstanding obligations under the Hercules Loan Agreement. This payoff amount included a final end of term charge to Hercules in the amount of $1.4 million, representing 6.7% of the aggregate original principal amount advanced by Hercules. Upon the payment of $12.4 million pursuant to the payoff letter, all outstanding indebtedness and obligations owed to Hercules under the Loan Agreement were deemed paid in full, and the Loan Agreement was terminated. At December 31, 2016, the Company had $13.1 million outstanding under the Hercules Loan Agreement and had accrued $1.1 million of the end of term charge.

In connection with the Hercules Loan Agreement, the Company issued to Hercules a warrant to purchase shares of the common stock of the Company at an exercise price of $60.50 per share. The warrant is exercisable for 17,190 shares of common stock. The warrant is exercisable until January 8, 2020. The Company estimated the fair value of the warrant for shares exercisable on the issue date in January 2015 to be $824,000. The value of the warrant was recorded as a discount to the loan and was being amortized to interest expense using the effective interest method over the term of the loan. The unamortized discount relating to the warrants, or $0.2 million, was expensed as interest expense upon repayment of the loan.

Stock-Based Compensation

6 Months Ended

Jun. 30, 2017

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Stock-Based Compensation

7.	STOCK-BASED COMPENSATION

In March 2014, the Company’s board of directors adopted and its stockholders approved the 2014 Stock Incentive Plan (the “2014 Plan”) and the 2014 Employee Stock Purchase Plan (the “ESPP”), which became effective in April 2014.

Stock Options

The 2014 Plan provides for the grant of incentive stock options, nonstatutory stock options, stock appreciation rights, restricted stock, restricted stock units and other stock-based awards. A summary of stock option activity for employee, director and nonemployee awards under all stock option plans during the six months ended June 30, 2017 is presented below (Aggregate Intrinsic Value in thousands):

	Number of Shares			Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Life (Years)		Aggregate Intrinsic Value
Outstanding at January 1, 2017		402,028		$	43.10		8.4	$	—
Granted		147,945		$	8.20
Exercised		—			—
Forfeited		(5,863	)	$	42.09
Outstanding at June 30, 2017		544,110		$	33.62		7.9	$	—
Options exercisable at June 30, 2017		220,497		$	47.92		7.6	$	—
Options vested and expected to vest at June 30, 2017		347,881		$	40.10		8.1	$	—

The weighted-average per share grant date fair value of options granted during the six months ended June 30, 2017 and 2016 was $4.38 and $13.10, respectively.

The fair value of each option award is estimated on the date of grant using the Black-Scholes option-pricing model based on the assumptions noted in the table below. Expected volatility for the Company’s common stock was determined based on an average of the historical volatility of a peer-group of similar public companies. The Company has limited option exercise information, and as such, the expected term of the options granted was calculated using the simplified method that represents the average of the contractual term of the option and the weighted-average vesting period of the option. The assumed dividend yield is based upon the Company’s expectation of not paying dividends in the foreseeable future. The risk-free rate for periods within the contractual life of the option is based upon the U.S. Treasury yield curve in effect at the time of grant.

The Company has recorded stock-based compensation expense related to the issuance of stock option awards to employees of $440,000 and $690,000 for the three months ended June 30, 2017 and 2016, respectively, and $1.4 million and $1.4 million for the six months ended June 30, 2017 and 2016, respectively. There were no stock options granted to employees during the three months ended June 30, 2017. The assumptions used in the Black-Scholes option-pricing model for stock options granted to employees and to directors in respect of board services during the three months ended June 30, 2016 and during the six months ended June 30, 2017 and 2016 are as follows:

	Three Months Ended June 30, 2016	Six Months Ended June 30,
	Three Months Ended June 30, 2016	2017	2016
Expected life	5.5 years	4.6 years	5.5-6.1 years
Risk-free interest rate	1.2%	1.8%	1.2%-1.9%
Expected volatility	61%	67%	61%
Expected dividend rate	—%	—%	—%

The Company recorded stock-based compensation expense related to nonemployee awards of $6,000 and $14,000 for the three months ended June 30, 2017 and 2016, respectively and $37,000 and $52,000 for the six months ended June 30, 2017 and 2016, respectively. The compensation expense related to nonemployee awards is included in the total stock-based compensation each year and is subject to re-measurement until the options vest. The fair value of the grants is being expensed over the vesting period of the options on a straight-line basis as the services are being provided. The Black-Scholes assumptions used to estimate fair value for the three and six months ended June 30, 2017 and 2016 were as follows:

	Three Months Ended June 30,		Six Months Ended June 30,
	2017	2016	2017	2016
Expected life	9.1-9.8 years	9.0-9.6 years	4.6-9.8 years	6.9-9.7 years
Risk-free interest rate	2.2%-2.4%	1.7%-2.0%	1.8%-2.4%	1.7%-2.0%
Expected volatility	74%-78%	61%	67%-77%	60%-61%
Expected dividend rate	—%	—%	—%	—%

During the six months ended June 30, 2017, the Company granted nonemployee stock options to purchase 15,100 shares of the Company’s common stock. There were no nonemployee stock option awards granted during the six months ended June 30, 2016. The weighted-average exercise price and the weighted-average grant date fair value of nonemployee stock options granted for the six months ended June 30, 2017 was $8.20 per share and $7.50 per share, respectively.

In March 2017, the Company extended the exercise period for all continuing employees’ stock options to two years beyond their termination date. These option modifications were initially accounted for in the quarter ended March 31, 2017. The increase of stock-based compensation related to these modifications was $16,000 and $283,000 for the three and six months ended June 30, 2017, respectively.

Employee Stock Purchase Plan

The ESPP permits eligible employees to enroll in a six-month offering period whereby participants may purchase shares of the Company’s common stock, through payroll deductions, at a price equal to 85% of the closing price of the common stock on the first day of the offering period or the last day of the offering period, whichever is lower. Purchase dates under the ESPP occur on or about June 30 and December 31 of each year. The board of directors determined not to initiate a new offering period beginning January 1, 2017. There was no stock-based compensation related to the ESPP for the three and six months ended June 30, 2017. The stock-based compensation expense related to the ESPP was $12,000 and $24,000 for the three months and six months ended June 30, 2016, respectively.

- Definition

The entire disclosure for compensation-related costs for equity-based compensation, which may include disclosure of policies, compensation plan details, allocation of equity compensation, incentive distributions, equity-based arrangements to obtain goods and services, deferred compensation arrangements, employee stock ownership plan details and employee stock purchase plan details.

+ References + Details

Fair Value Measurements

6 Months Ended

Jun. 30, 2017

Fair Value Disclosures [Abstract]

Fair Value Measurements

8.	FAIR VALUE MEASUREMENTS

The Company’s financial instruments consist of cash equivalents, accounts payable, accrued expenses, and debt obligations. The carrying amount of accounts payable and accrued expenses are considered a reasonable estimate of their fair value, due to the short-term maturity of these instruments. The carrying amount of debt is also considered to be a reasonable estimate of its fair value based on the short term nature of the debt and because the debt bears interest at the prevailing market rate for instruments with similar characteristics.

Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Valuation techniques used to measure fair value are performed in a manner to maximize the use of observable inputs and minimize the use of unobservable inputs.

The accounting standard describes a fair value hierarchy based on three levels of inputs, of which the first two are considered observable and the last unobservable, that may be used to measure fair value, which are the following:

Level 1 — Quoted prices (unadjusted) in active markets that are accessible at the market date for identical unrestricted assets or liabilities.

Level 2 — Inputs other than Level 1 that are observable, either directly or indirectly, such as quoted prices for similar assets or liabilities; quoted prices in markets that are not active; or other inputs for which all significant inputs are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities.

Level 3 — Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities.

A summary of the financial assets and liabilities that are measured on a recurring basis at fair value as of June 30, 2017 and December 31, 2016, is as follows (in thousands):

			Fair Value Measurements Using
	Carrying		Quoted Prices in Active Markets for Identical Assets		Significant Other Observable Inputs		Significant Unobservable Inputs
	Value		(Level 1)		(Level 2)		(Level 3)
June 30, 2017
Money market funds	$	7,014	$	—	$	7,014	$	—
December 31, 2016
Money market funds	$	34,950	$	—	$	34,950	$	—

The Company believes that its debt obligations bear interest at rates which approximate prevailing market rates for instruments with similar characteristics and, accordingly, the carrying values for these instruments approximate fair value. The Company’s debt obligations are Level 2 measurements in the fair value hierarchy.

The Company’s money market funds have been valued on the basis of valuations provided by third-party pricing services, as derived from such services’ pricing models. Inputs to the models may include, but are not limited to, reported trades, executable bid and asked prices, broker/dealer quotations, prices or yields of securities with similar characteristics, benchmark curves or information pertaining to the issuer, as well as industry and economic events. The pricing services may use a matrix approach, which considers information regarding securities with similar characteristics to determine the valuation for a security. The Company is ultimately responsible for the consolidated financial statements and underlying estimates. Accordingly, the Company assesses the reasonableness of the valuations provided by the third-party pricing services by reviewing actual trade data, broker/dealer quotes and other similar data, which are obtained from quoted market prices or other sources.

No transfers between levels occurred during the periods presented.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Revenue

6 Months Ended

Jun. 30, 2017

Research And Development [Abstract]

Revenue

REVENUE

In October 2016, the Company entered into a research collaboration agreement with Novartis pursuant to which the Company granted to Novartis certain exclusive, world-wide licenses to the Company’s intellectual property relating to its platform technology and know-how. Under the collaboration, the Company and Novartis agreed to collaborate, over an initial research term of two years, with respect to the pre-clinical development of nanoparticle drug conjugates comprised of the Company’s proprietary polymer covalently linked to Novartis-selected active pharmaceutical ingredients for up to five targets to be agreed upon by the Company and Novartis. In October 2016, the Company received a $5.0 million upfront payment under the collaboration which it will recognize on a straight-line basis over the initial term of the collaboration. The Company will also receive funding from Novartis for up to five full-time employees of the Company to be engaged in activities under the collaboration during the research term. For the three and six months ended June 30, 2017, the Company recognized revenue of $625,000 and $1.3 million, respectively, in connection with the upfront fee, and $17,000 and $584,000, respectively, in connection with the funding for activities performed under the collaboration during the research term.

- Definition

The entire disclosure for research, development, and computer software activities, including contracts and arrangements to be performed for others and with federal government. Includes costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility and in-process research and development acquired in a business combination consummated during the period.

+ References + Details

Restructuring

6 Months Ended

Jun. 30, 2017

Restructuring And Related Activities [Abstract]

Restructuring

10.	RESTRUCTURING

On March 19, 2017, the Company entered into retention agreements with certain executive officers. These retention agreements supersede the provisions of such executive officers’ employment agreements and retention letters with the Company providing for post-separation benefits, and provide for certain lump sum payments ranging from six to 18 months of salary, plus health and dental insurance coverage, while also providing the covered executives with a cash bonus upon completion of a change in control. The Company paid $1.1 million under the terms of the retention agreements on March 31, 2017 which was recorded as a prepaid expense. Under the terms of the retention agreements, the retention payments are earned upon continued employment with the Company for the retention period of three or six months, as specified in the retention agreements, unless earlier released by the Company. During the three months ended June 30, 2017, $923,000 of the retention payments was earned and recognized in operating expenses. In addition, under the terms of the retention agreements, the Company may be required to pay up to an additional $1.6 million of change in control and severance payments.

On March 19, 2017, the board of directors approved an amendment of the Company’s existing options to provide that, notwithstanding each such option’s original vesting schedule and notwithstanding that the option holder’s service with the Company may have terminated prior to the closing of a change in control, effective immediately prior to a change in control, the vesting schedule of each such option would be accelerated in full so that all shares would immediately become vested and exercisable, or, if shorter, in accordance with the original vesting schedule set forth in the applicable option award agreement. The Board also approved an amendment of all existing options to provide that, notwithstanding each such option’s original terms effective on the date thereof, the period during which such option holder may exercise his or her stock options that are vested on the date of his or her termination of service with the Company would be extended until the date two (2) years following the date the option holder ceased providing service to the Company, provided that in no event may such option be exercised following the end of the original term of such option.

Subsequent Events

6 Months Ended

Jun. 30, 2017

Subsequent Events [Abstract]

Subsequent Events

11.	SUBSEQUENT EVENTS

Stock Purchase, Reverse Stock Split, Name Change, and Related Transactions

As described in Note 1, “Nature of Business and Operations,” on July 19, 2017, the Company completed the stock purchase of Private Daré. Pursuant to the terms of the Stock Purchase Agreement, Cerulean issued shares of its common stock to Private Daré stockholders at an exchange ratio of 2.029969 shares of its common stock for each one share of Private Daré common stock outstanding before giving effect to the Reverse Stock Split. In addition, the Company assumed all outstanding options to purchase shares of Private Daré common stock, which options converted into options to purchase shares of its common stock, appropriately adjusted based on the exchange ratio. As a result of such issuance of shares, the stockholders of Private Daré became the majority stockholders of the Company.

The Stock Purchase Transaction will be accounted for as a “reverse merger” under the acquisition method of accounting for business combinations with Private Daré treated as the accounting acquirer. Private Daré was determined to be the accounting acquirer based upon the terms of the Stock Purchase Transaction and other factors, such as relative voting rights and the composition of the combined company’s board of directors and senior management. All of the assets and liabilities of the Company will be recorded at their respective fair values as of the acquisition date and consolidated with those of Private Daré. Transaction costs will be expensed as incurred.

Given the timing of the closing of the Stock Purchase Transaction, the purchase accounting is incomplete at this time. As such, it is not practicable for the Company to disclose the allocation of purchase price to assets acquired and liabilities assumed and pro forma revenues and earnings of the combined entity. The fair value of the consideration transferred in the Stock Purchase Transaction will be measured using the closing trading price of the Company’s common stock on July 19, 2017, the closing date of the Stock Purchase Transaction. This information will be included in the Company’s Quarterly Report on Form 10-Q for the fiscal quarter ended September 30, 2017 and in a Form 8-K/A to be filed with the SEC.

On July 19, 2017, the Company completed the sale to Novartis of all of its right, title and interest in and to the patent rights, know-how and third-party license agreements relating to the Platform pursuant to the Novartis Asset Purchase Agreement dated March 19, 2017. At the closing of the transaction, Novartis paid the Company $6.0 million.

On July 20, 2017, the Company effected the Reverse Stock Split and changed its name to Daré Bioscience, Inc.

Prior to the closing of the Stock Purchase Transaction, the Company’s stock was listed on The Nasdaq Capital Market under the ticker symbol “CERU.” On July 20, 2017, the Company’s common stock commenced trading on The Nasdaq Capital Market (on a Reverse Stock Split-adjusted basis) under the ticker symbol “DARE.”

Significant Accounting Policies (Policies)	6 Months Ended
Significant Accounting Policies (Policies)	Jun. 30, 2017
Accounting Policies [Abstract]
Recent Accounting Pronouncements	Recent Accounting Pronouncements — In November 2016, the Financial Accounting Standards Board (the “FASB”) issued Accounting Standards Update 2016-18, “Statement of Cash Flows - Restricted Cash (Topic 230)”. This new standard requires companies to include amounts generally described as restricted cash and restricted cash equivalents in cash and cash equivalents when reconciling beginning-of-period and end-of-period total amounts shown on the statement of cash flows. This guidance is effective for annual and interim reporting periods beginning after December 15, 2017, and required retrospective application. The Company is currently evaluating the effect this standard will have on its consolidated financial statements and related disclosures. In August 2016, the FASB issued Accounting Standards Update 2016-15, “Statement of Cash Flows (Topic 230)” (“ASU 2016-15”). ASU 2016-15 provides guidance to clarify how cash payments for debt prepayment or debt extinguishment costs are to be classified in the statement of cash flows. The standard is effective for financial statements issued for fiscal years beginning after December 15, 2017, and interim periods within those fiscal years. The Company is currently evaluating the effect this standard will have on its consolidated financial statements and related disclosures. In February 2016, the FASB issued Accounting Standards Update 2016-02, “Leases (Topic 842)” (“ASU 2016-02”), which provides new accounting guidance on leases. ASU 2016-02 requires lessees to recognize leases on their balance sheets, and leaves lessor accounting largely unchanged. The amendments in ASU 2016-02 are effective for fiscal years beginning after December 15, 2018 and interim periods within those fiscal years. Early application is permitted for all entities. ASU 2016-02 requires a modified retrospective approach for all leases existing at, or entered into after, the date of initial application, with an option to elect to use certain transition relief. The Company is currently evaluating the impact of this new standard on its consolidated financial statements and related disclosures. In May 2014, the FASB issued Accounting Standards Update 2014-09 (ASC 606), “Revenue from Contracts with Customers” (ASU 2015-09), which affects any entity that either enters into contracts with customers to transfer goods and services or enters into contracts for the transfer of nonfinancial assets. In August 2015, the FASB issued Accounting Standards Update 2015-14, “Revenue from Contracts with Customers” which defers the effective date of ASU 2014-09 for all entities by one year. ASU 2014-09, which has been codified with the Accounting Standards Codification as Topic 606, is now effective for public companies for annual reporting periods beginning after December 15, 2017, including interim periods within those reporting periods. ASC 606 outlines a single comprehensive model for entities to use in accounting for revenue arising from contracts with customers and supersedes most current revenue recognition guidance, including industry-specific guidance. In addition, ASC 606 provides guidance on accounting for certain revenue-related costs including, but not limited to, when to capitalize costs associated with obtaining and fulfilling a contract. ASC 606 provides companies with two implementation methods. Companies can choose to apply the standard retrospectively to each prior reporting period presented (full retrospective application) or retrospectively with the cumulative effect of initially applying the standard as an adjustment to the opening balance of retained earnings of the annual reporting period that includes the date of initial application (modified retrospective application). Since ASU 2014-09 was issued, several additional Accounting Standards Updates have been issued and incorporated within ASC 606 to clarify various elements of the guidance. The Company plans to adopt this guidance on January 1, 2018. The Company has not yet determined whether it will utilize the full retrospective or the modified retrospective adoption method and continues to evaluate the impact that adoption will have on its consolidated financial statements.

Net Loss Per Share Attributable to Common Stockholders (Tables)

6 Months Ended

Jun. 30, 2017

Earnings Per Share [Abstract]

Potentially Dilutive Securities Excluded from Computation of Diluted Weighted-Average Shares Outstanding

	As of June 30,
	2017		2016
Options to purchase common stock		544,110		414,598
Warrants to purchase common stock		30,503		36,556

Property and Equipment (Tables)

6 Months Ended

Jun. 30, 2017

Property Plant And Equipment [Abstract]

Summary of Property and Equipment

Property and equipment consists of the following (in thousands):

	As of June 30, 2017			As of December 31, 2016
Laboratory equipment	$	—		$	1,548
Computer equipment		100			371
Office furniture and equipment		—			66
Leasehold improvements		—			75
		100			2,060
Less accumulated depreciation and amortization		(83	)		(1,392	)
Property and equipment, net	$	17		$	668

Accrued Expenses (Tables)

6 Months Ended

Jun. 30, 2017

Payables And Accruals [Abstract]

Schedule of Accrued Expenses

Accrued expenses consist of the following (in thousands):

	As of June 30, 2017		As of December 31, 2016
Accrued clinical trial costs	$	25	$	2,648
Accrued contract manufacturing expenses		—		226
Accrued compensation and benefits		44		1,080
Accrued interest		—		82
Other accrued expenses		120		575
Total accrued expenses	$	189	$	4,611

Stock-Based Compensation (Tables)

6 Months Ended

Jun. 30, 2017

Summary of Stock Option Activity for Employee, Director and Nonemployee Awards

A summary of stock option activity for employee, director and nonemployee awards under all stock option plans during the six months ended June 30, 2017 is presented below (Aggregate Intrinsic Value in thousands):

	Number of Shares			Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Life (Years)		Aggregate Intrinsic Value
Outstanding at January 1, 2017		402,028		$	43.10		8.4	$	—
Granted		147,945		$	8.20
Exercised		—			—
Forfeited		(5,863	)	$	42.09
Outstanding at June 30, 2017		544,110		$	33.62		7.9	$	—
Options exercisable at June 30, 2017		220,497		$	47.92		7.6	$	—
Options vested and expected to vest at June 30, 2017		347,881		$	40.10		8.1	$	—

Summary of Assumptions Used in Black-Scholes Option-Pricing Model for Stock Options Granted to Employees, Directors and Non Employees

The assumptions used in the Black-Scholes option-pricing model for stock options granted to employees and to directors in respect of board services during the three months ended June 30, 2016 and during the six months ended June 30, 2017 and 2016 are as follows:

	Three Months Ended June 30, 2016	Six Months Ended June 30,
	Three Months Ended June 30, 2016	2017	2016
Expected life	5.5 years	4.6 years	5.5-6.1 years
Risk-free interest rate	1.2%	1.8%	1.2%-1.9%
Expected volatility	61%	67%	61%
Expected dividend rate	—%	—%	—%

Non Employee Awards [Member]

Summary of Assumptions Used in Black-Scholes Option-Pricing Model for Stock Options Granted to Employees, Directors and Non Employees

The fair value of the grants is being expensed over the vesting period of the options on a straight-line basis as the services are being provided. The Black-Scholes assumptions used to estimate fair value for the three and six months ended June 30, 2017 and 2016 were as follows:

	Three Months Ended June 30,		Six Months Ended June 30,
	2017	2016	2017	2016
Expected life	9.1-9.8 years	9.0-9.6 years	4.6-9.8 years	6.9-9.7 years
Risk-free interest rate	2.2%-2.4%	1.7%-2.0%	1.8%-2.4%	1.7%-2.0%
Expected volatility	74%-78%	61%	67%-77%	60%-61%
Expected dividend rate	—%	—%	—%	—%

Fair Value Measurements (Tables)

6 Months Ended

Jun. 30, 2017

Fair Value Disclosures [Abstract]

Summary of Financial Assets and Liabilities Measured on Recurring Basis at Fair Value

A summary of the financial assets and liabilities that are measured on a recurring basis at fair value as of June 30, 2017 and December 31, 2016, is as follows (in thousands):

			Fair Value Measurements Using
	Carrying		Quoted Prices in Active Markets for Identical Assets		Significant Other Observable Inputs		Significant Unobservable Inputs
	Value		(Level 1)		(Level 2)		(Level 3)
June 30, 2017
Money market funds	$	7,014	$	—	$	7,014	$	—
December 31, 2016
Money market funds	$	34,950	$	—	$	34,950	$	—

Nature of Business and Operations - Additional Information (Detail) $ / shares in Units, $ in Millions			6 Months Ended
	Jul. 20, 2017 $ / shares	Jul. 19, 2017 USD ($)	Jun. 30, 2017 $ / shares	Dec. 31, 2016 $ / shares
Nature Of Business And Operations [Line Items]
Stock purchase agreement date			Mar. 19, 2017
Stock purchase transaction completion date			Jul. 19, 2017
Common stock, par value			$ 0.0001	$ 0.0001
Subsequent Events [Member]
Nature Of Business And Operations [Line Items]
Reverse stock split description	1-for-10
Reverse stock split ratio	0.1
Common stock, par value	$ 0.0001
Subsequent Events [Member] \| Novartis Institutes for BioMedical Research, Inc [Member] \| Asset Purchase Agreement [Member]
Nature Of Business And Operations [Line Items]
Proceeds from sale of assets \| $		$ 6.0
Existing resources sufficient to fund planned operations, term		2 years

Net Loss Per Share Attributable to Common Stockholders - Potentially Dilutive Securities Excluded from Computation of Diluted Weighted-Average Shares Outstanding (Detail) - shares	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Options to Purchase Common Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of diluted weighted-average shares outstanding	544,110	414,598
Warrants [Member] \| Common Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of diluted weighted-average shares outstanding	30,503	36,556

Property and Equipment - Summary of Property and Equipment (Detail) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 100	$ 2,060
Less accumulated depreciation and amortization	(83)	(1,392)
Property and equipment, net	17	668
Laboratory Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross		1,548
Computer Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 100	371
Office Furniture and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross		66
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross		$ 75

Property and Equipment - Additional Information (Detail) - USD ($)	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Property, Plant and Equipment [Line Items]
Charges for disposal of property and equipment	$ 177,000	$ 4,000
Lease termination agreement date	May 31, 2017
Discontinued Operations, Held-for-sale [Member] \| Other Expense [Member]
Property, Plant and Equipment [Line Items]
Charges for disposal of property and equipment	$ 177,000

Accrued Expenses - Schedule of Accrued Expenses (Detail) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Payables And Accruals [Abstract]
Accrued clinical trial costs	$ 25	$ 2,648
Accrued contract manufacturing expenses		226
Accrued compensation and benefits	44	1,080
Accrued interest		82
Other accrued expenses	120	575
Total accrued expenses	$ 189	$ 4,611

Loan Agreements - Additional Information (Detail) - Hercules Loan Agreement [Member] - Hercules Technology Growth Capital, Inc. [Member] - USD ($)		6 Months Ended
	Mar. 20, 2017	Jun. 30, 2017	Dec. 31, 2016	Jan. 31, 2015	Jan. 08, 2015
Debt Instrument [Line Items]
Loan and security agreement, maximum borrowing capacity					$ 26,000,000
Pay off loan agreement, amount paid	$ 12,400,000
Pay off loan agreement, final end of term charge amount	$ 1,400,000
Final payment as percentage of aggregate original principal amount	6.70%
Amount outstanding under the loan and security agreement			$ 13,100,000
Accrued end of term charge			$ 1,100,000
Class of warrant or right, date until which warrants exercisable		Jan. 08, 2020
Estimated fair value of warrant				$ 824,000
Loans Payable [Member]
Debt Instrument [Line Items]
Unamortized discount on debt, relating to warrants	$ 200,000
Common Stock [Member]
Debt Instrument [Line Items]
Exercise price of warrant					$ 60.50
Warrant to purchase stock, number of securities called by warrants or rights					17,190

Stock-Based Compensation - Summary of Stock Option Activity for Employee, Director and Nonemployee Awards (Detail)	6 Months Ended	12 Months Ended
	Jun. 30, 2017 $ / shares shares	Dec. 31, 2016 $ / shares shares
Number of shares
Number of Shares, Outstanding \| shares	402,028
Number of Shares, Granted \| shares	147,945
Number of Shares, Forfeited \| shares	(5,863)
Number of Shares, Outstanding \| shares	544,110	402,028
Number of Shares, Options exercisable \| shares	220,497
Number of Shares, Options vested and expected to vest \| shares	347,881
Weighted-Average Exercise Price
Weighted-Average Exercise Price, Outstanding \| $ / shares	$ 43.10
Weighted-Average Exercise Price, Granted \| $ / shares	8.20
Weighted-Average Exercise Price, Forfeited \| $ / shares	42.09
Weighted-Average Exercise Price, Outstanding \| $ / shares	33.62	$ 43.10
Weighted-Average Exercise Price, Options exercisable \| $ / shares	47.92
Weighted-Average Exercise Price, Options vested and expected to vest \| $ / shares	$ 40.10
Weighted-Average Remaining Contractual Life (Years)
Weighted-Average Remaining Contractual Life (Years)	7 years 10 months 25 days	8 years 4 months 24 days
Weighted-Average Remaining Contractual Life (Years), Options exercisable	7 years 7 months 6 days
Weighted-Average Remaining Contractual Life (Years), Options vested and expected to vest	8 years 1 month 6 days

Stock-Based Compensation - Additional Information (Detail) - USD ($)	1 Months Ended	3 Months Ended		6 Months Ended
	Mar. 31, 2017	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Shares, Granted				147,945
Weighted-Average Exercise Price, Options exercisable		$ 47.92		$ 47.92
Employee Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense		$ 16,000		$ 283,000
Exercise period for emoloyees' stock options after termination date	2 years
2014 Stock Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average per share grant date fair value of options granted				$ 4.38	$ 13.10
2014 Stock Incentive Plan [Member] \| Employee Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense		$ 440,000	$ 690,000	$ 1,400,000	$ 1,400,000
Number of Shares, Granted		0
2014 Stock Incentive Plan [Member] \| Non Employee Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average per share grant date fair value of options granted				$ 7.50
Stock-based compensation expense		$ 6,000	14,000	$ 37,000	$ 52,000
Number of Shares, Granted				15,100	0
Weighted-Average Exercise Price, Options exercisable		$ 8.20		$ 8.20
2014 Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense		$ 0	$ 12,000	$ 0	$ 24,000
Purchase price as percentage of stock price on offering period				85.00%
Offering period				6 months

Stock-Based Compensation - Summary of Assumptions Used in Black-Scholes Option-Pricing Model for Stock Options Granted to Employees, Directors and Non Employees (Detail)	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected life		5 years 6 months	4 years 7 months 6 days
Risk-free interest rate		1.20%	1.80%
Risk-free interest rate, minimum				1.20%
Risk-free interest rate, maximum				1.90%
Expected volatility		61.00%	67.00%	61.00%
Expected dividend rate		0.00%	0.00%	0.00%
Non Employee Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate, minimum	2.20%	1.70%	1.80%	1.70%
Risk-free interest rate, maximum	2.40%	2.00%	2.40%	2.00%
Expected volatility		61.00%
Expected volatility, minimum	74.00%		67.00%	60.00%
Expected volatility, maximum	78.00%		77.00%	61.00%
Expected dividend rate	0.00%	0.00%	0.00%	0.00%
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected life				5 years 6 months
Minimum [Member] \| Non Employee Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected life	9 years 1 month 6 days	9 years	4 years 7 months 6 days	6 years 10 months 25 days
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected life				6 years 1 month 6 days
Maximum [Member] \| Non Employee Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected life	9 years 9 months 18 days	9 years 7 months 6 days	9 years 9 months 18 days	9 years 8 months 12 days

Fair Value Measurements - Summary of Financial Assets and Liabilities Measured on Recurring Basis at Fair Value (Detail) - Fair Value, Measurements, Recurring [Member] - Money Market Funds [Member] - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Carrying Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Money market funds	$ 7,014	$ 34,950
Fair Value Measurements [Member] \| Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Money market funds	$ 7,014	$ 34,950

Revenue - Additional Information (Detail)	1 Months Ended	3 Months Ended	6 Months Ended
Revenue - Additional Information (Detail)	Oct. 31, 2016 USD ($) Employee	Jun. 30, 2017 USD ($)	Jun. 30, 2017 USD ($)
Revenue Recognition, Milestone Method [Line Items]
Revenue		$ 642,000	$ 1,834,000
Novartis Institutes for BioMedical Research, Inc [Member] \| Collaboration Agreement [Member]
Revenue Recognition, Milestone Method [Line Items]
Initial research term of agreement	2 years
Upfront payment received	$ 5,000,000
Number of full-time employees engaged in research activities under the collaboration \| Employee	5
Novartis Institutes for BioMedical Research, Inc [Member] \| Upfront Fee [Member] \| Collaboration Agreement [Member]
Revenue Recognition, Milestone Method [Line Items]
Revenue		625,000	1,300,000
Novartis Institutes for BioMedical Research, Inc [Member] \| Funding for Activities Performed [Member] \| Collaboration Agreement [Member]
Revenue Recognition, Milestone Method [Line Items]
Revenue		$ 17,000	$ 584,000

Restructuring - Additional Information (Detail) - Certain Executive Officers [Member] - USD ($)		3 Months Ended
	Mar. 19, 2017	Jun. 30, 2017	Mar. 31, 2017
Restructuring Cost and Reserve [Line Items]
Amount paid under terms of the retention agreements			$ 1,100,000
Retention payments recognized in operating expenses		$ 923,000
Stock options exercise period extended upon approval of amendment	2 years
Maximum [Member]
Restructuring Cost and Reserve [Line Items]
Retention agreements period of salary compensation as lump sum payments (in months)	18 months
Amount required to pay under retention agreements	$ 1,600,000
Minimum [Member]
Restructuring Cost and Reserve [Line Items]
Retention agreements period of salary compensation as lump sum payments (in months)	6 months

Subsequent Events - Additional Information (Detail) - USD ($) $ in Millions		6 Months Ended
	Jul. 19, 2017	Jun. 30, 2017
Private Dare [Member]
Subsequent Event [Line Items]
Stock purchase transaction completion date		Jul. 19, 2017
Subsequent Events [Member] \| Novartis Institutes for BioMedical Research, Inc [Member] \| Asset Purchase Agreement [Member]
Subsequent Event [Line Items]
Proceeds from sale of assets	$ 6.0
Subsequent Events [Member] \| Common Stock [Member] \| Private Dare [Member] \| Stock Purchase Agreement [Member]
Subsequent Event [Line Items]
Stock purchase agreement, description	Cerulean issued shares of its common stock to Private Daré stockholders at an exchange ratio of 2.029969 shares of its common stock for each one share of Private Daré common stock outstanding before giving effect to the Reverse Stock Split. In addition, the Company assumed all outstanding options to purchase shares of Private Daré common stock, which options converted into options to purchase shares of its common stock, appropriately adjusted based on the exchange ratio. As a result of such issuance of shares, the stockholders of Private Daré became the majority stockholders of the Company.
Number of shares issued for each share under exchange ratio	2.029969