Collaboration Agreements (Details)		1 Months Ended				3 Months Ended					9 Months Ended		12 Months Ended	21 Months Ended
	Sep. 07, 2016 USD ($) shares	Oct. 31, 2016 USD ($) program	Sep. 30, 2016 USD ($) program shares	Jan. 31, 2015	Jun. 30, 2003 USD ($)	Sep. 30, 2016 USD ($) program	Jun. 30, 2016 USD ($)	Mar. 31, 2016 USD ($)	Dec. 31, 2015 USD ($) payment right product term program patient	Sep. 30, 2015 USD ($)	Sep. 30, 2016 USD ($) program	Sep. 30, 2015 USD ($)	Dec. 31, 2015 USD ($) payment right product term program patient	Sep. 30, 2016 USD ($) program	Sep. 06, 2016 $ / shares	Oct. 31, 2015 USD ($) program	Dec. 31, 2012 USD ($)
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Recognized royalty revenue						$ 1,817,000				$ 2,293,000	$ 5,403,000	$ 5,998,000
Cost of royalty revenues						94,000				116,000	278,000	303,000
Collaboration agreement, number of optional additional terms | term									3				3
Collaboration agreement, optional additional term													1 year
Option fees													$ 7,500,000
Number of payments | payment									2				2
Closing share price of common stock (in dollars per share) | $ / shares															$ 1.76
Curis Royalty | Credit agreement with BioPharma-II
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Principal loan amount to Curis Royalty given by BioPharma under credit agreement																	$ 30,000,000
Interest rate on loan to Curis Royalty given by BioPharma under credit agreement																	12.25%
Genentech, Inc.
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Amount received for specified clinical development and regulatory objectives			$ 59,000,000			59,000,000					59,000,000			$ 59,000,000
Percentage of royalty rate decrease					2.00%				2.00%
Recognized royalty revenue						1,800,000				2,300,000	5,400,000	6,000,000
Cost of royalty revenues						$ 100,000				$ 100,000	$ 300,000	$ 300,000
Percentage of royalties earned						5.00%				5.00%	5.00%	5.00%
Genentech, Inc. | Drug development royalty
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Research and development revenue						$ 100,000				$ 100,000	$ 200,000	$ 200,000
Research and development expenses						$ 100,000				$ 300,000	$ 400,000	$ 400,000
Genentech, Inc. | Maximum
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Eligible to receive contingent cash payment for specified clinical development and regulatory objectives (up to)					$ 115,000,000
Percentage of royalty on net sales					7.50%
Genentech, Inc. | Minimum
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Percentage of royalty on net sales					5.00%
Aurigene
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Collaboration agreement, option exercisable period				90 days
Collaboration agreement, number of programs licensed | program			2			2			2		2		2	2		2
Collaboration agreement payment													$ 6,000,000
Additional payments made under collaborative arrangements (up to)																$ 2,000,000
Research and development expenses						$ 18,000,000		$ 1,000,000	$ 1,000,000		$ 18,000,000
Payments for research and development							$ 1,000,000	$ 1,000,000
Payment for preclinical program for potential further development													$ 2,000,000
Collaboration agreement, number of products required to commercialize (at least) | product									1				1
Collaboration agreement period													2 years
Collaboration agreement, rights granted to nominate global drug substance or drug product supplier | right									1				1
Payments made under collaboration arrangements														$ 11,000,000
Shares issued of common stock in exchange for waived payment (in shares) | shares	10,208,333		10,208,333
Waived payment of milestone and other payments (up to)	$ 24,500,000		$ 24,500,000
Value of common stock issued	18,000,000
Aurigene | Subsequent event
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Collaboration agreement, number of programs licensed | program		3
Payment for license and designation as the development candidate		$ 1,500,000
Aurigene | PD1/VISTA programs
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Collaboration agreement payment													$ 3,000,000
Collaboration agreement expenses, option exercise													3,000,000
Collaboration agreement expenses, acceptance of IND filing						3,000,000							3,000,000
Collaboration agreement expenses, dosing of fifth patient													4,000,000
Aurigene | IRAK4 programs
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Collaboration agreement payment													3,000,000
Collaboration agreement expenses, option exercise													3,000,000
Collaboration agreement expenses, acceptance of IND filing													3,000,000
Collaboration agreement expenses, dosing of fifth patient													4,000,000
Aurigene | Programs three and four
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Agreement to provide additional funding, if options are exercised (up to)	2,000,000
Aurigene | Program three
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Collaboration agreement expenses, option exercise													3,000,000
Collaboration agreement expenses, acceptance of IND filing													2,500,000
Payments made under collaboration arrangements														2,000,000
Collaboration agreement expenses, program selection fee													2,000,000
Aurigene | Program four
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Collaboration agreement expenses, option exercise													3,000,000
Collaboration agreement expenses, acceptance of IND filing													2,500,000
Collaboration agreement expenses, program selection fee													2,000,000
Aurigene | Program thereafter
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Additional payments made under collaborative arrangements (up to)			$ 0			$ 0					$ 0			$ 0
Collaboration agreement, fees (up to)													$ 53,000,000
Aurigene | Extended exclusivity, IRAK4 program
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Waived payment of milestone and other payments (up to)	1,000,000
Aurigene | Acceptance of IND filing, IRAK4 program
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Waived payment of milestone and other payments (up to)	3,000,000
Aurigene | Phase 1 clinical trial, dosing of fifth patient, IRAK4 program
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Waived payment of milestone and other payments (up to)	4,000,000
Number of patients dosed that trigger payment | patient									5,000				5,000
Aurigene | Extended exclusivity, PD1/VISTA program
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Waived payment of milestone and other payments (up to)	1,000,000
Aurigene | Phase 1 clinical trial, dosing of fifth patient, PD1/VISTA
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Waived payment of milestone and other payments (up to)	4,000,000
Number of patients dosed that trigger payment | patient									5,000				5,000
Aurigene | Option exercise payment, program three
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Waived payment of milestone and other payments (up to)	$ 1,500,000
Percentage of consideration received	50.00%
Aurigene | Acceptance of IND filing, program three
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Waived payment of milestone and other payments (up to)	$ 2,500,000
Aurigene | Program selection fee, program four
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Waived payment of milestone and other payments (up to)	2,000,000
Aurigene | Option exercise payment, program four
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Waived payment of milestone and other payments (up to)	3,000,000
Aurigene | Acceptance of IND filing, program four
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Waived payment of milestone and other payments (up to)	$ 2,500,000
Aurigene | Maximum
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Collaboration agreement period													5 years
Percentage of contribution (up to)									50.00%				50.00%
Aurigene | Maximum | PD1/VISTA programs
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Collaboration agreement, payment per program (up to)													$ 52,500,000
Aurigene | Maximum | IRAK4 programs
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Collaboration agreement, payment per program (up to)													52,500,000.0
Aurigene | Maximum | Program three
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Collaboration agreement, payment per program (up to)													50,000,000
Aurigene | Maximum | Program four
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Collaboration agreement, payment per program (up to)													50,000,000.0
Aurigene | Maximum | Program thereafter
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Collaboration agreement, payment per program (up to)													$ 140,500,000