Share-Based Compensation - Share-based Compensation Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based compensation	$ (41,589)	$ (23,743)	$ (19,469)
Equity awards compensation expense	(43,259)	(23,989)	(19,600)
R&D
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based compensation	(12,108)	(6,520)	(3,682)
Equity awards compensation expense	(12,108)	(6,520)	(3,682)
S&O
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based compensation	(16,838)	(11,678)	(12,290)
Equity awards compensation expense	(16,838)	(11,678)	(12,290)
G&A
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based compensation	(12,643)	(5,545)	(3,497)
Equity awards compensation expense	(14,313)	(5,791)	(3,628)
RSUs
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based compensation	(29,170)	(2,296)	0
RSUs | R&D
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based compensation	(9,178)	(706)	0
RSUs | S&O
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based compensation	(12,705)	(1,046)	0
RSUs | G&A
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based compensation	(7,287)	(544)	0
OSA and BSPCE
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based compensation	(12,419)	(21,447)	(19,469)
OSA and BSPCE | R&D
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based compensation	(2,930)	(5,814)	(3,682)
OSA and BSPCE | S&O
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based compensation	(4,133)	(10,632)	(12,290)
OSA and BSPCE | G&A
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based compensation	(5,356)	(5,001)	(3,497)
Plan 3 | OSA and BSPCE
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based compensation	0	(5)	13
Plan 3 | OSA and BSPCE | R&D
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based compensation	0	1	34
Plan 3 | OSA and BSPCE | S&O
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based compensation	0	(6)	15
Plan 3 | OSA and BSPCE | G&A
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based compensation	0	0	(36)
Plan 5 | OSA and BSPCE
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based compensation	(42)	(152)	(606)
Plan 5 | OSA and BSPCE | R&D
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based compensation	(8)	(71)	(215)
Plan 5 | OSA and BSPCE | S&O
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based compensation	(27)	27	(134)
Plan 5 | OSA and BSPCE | G&A
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based compensation	(7)	(108)	(257)
Plan 6 | OSA and BSPCE
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based compensation	(217)	(585)	(1,907)
Plan 6 | OSA and BSPCE | R&D
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based compensation	(35)	(188)	(505)
Plan 6 | OSA and BSPCE | S&O
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based compensation	(20)	(384)	(1,358)
Plan 6 | OSA and BSPCE | G&A
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based compensation	(162)	(13)	(44)
Plan 7 | OSA and BSPCE
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based compensation	(189)	(3,021)	(11,226)
Plan 7 | OSA and BSPCE | R&D
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based compensation	(234)	(884)	(1,598)
Plan 7 | OSA and BSPCE | S&O
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based compensation	239	(1,758)	(8,494)
Plan 7 | OSA and BSPCE | G&A
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based compensation	(194)	(379)	(1,134)
Plan 8 | OSA and BSPCE
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based compensation	(11,483)	(17,684)	(5,743)
Plan 8 | OSA and BSPCE | R&D
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based compensation	(2,587)	(4,672)	(1,398)
Plan 8 | OSA and BSPCE | S&O
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based compensation	(4,258)	(8,511)	(2,319)
Plan 8 | OSA and BSPCE | G&A
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based compensation	(4,638)	(4,501)	(2,026)
Plan 9 | OSA and BSPCE
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based compensation	(488)	0	0
Plan 9 | OSA and BSPCE | R&D
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based compensation	(66)	0	0
Plan 9 | OSA and BSPCE | S&O
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based compensation	(67)	0	0
Plan 9 | OSA and BSPCE | G&A
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based compensation	(355)	0	0
BSA | BSA
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Issuance of non-employee warrants	(1,670)	(246)	(131)
BSA | BSA | R&D
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Issuance of non-employee warrants	0	0	0
BSA | BSA | S&O
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Issuance of non-employee warrants	0	0	0
BSA | BSA | G&A
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Issuance of non-employee warrants	$ (1,670)	$ (246)	$ (131)