Contingently Issuable Common Stock (Details) - USD ($) $ / shares in Units, $ in Thousands, shares in Millions			12 Months Ended
	Jun. 17, 2014	Dec. 10, 2010	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Jun. 16, 2014
Fair Value of Contingently Issuable Common Stock [Roll Forward]
Fair value of contingent payment, beginning balance			$ 14,700
Change in fair value of contingent consideration related to acquisition			(2,500)	$ 100	$ (7,928)
Fair value of contingent payment, ending balance			$ 12,200	$ 14,700
Nelix Milestones
Business Acquisition [Line Items]
Purchase price of common shares (in shares)			2.0
Contingently issuable shares (in shares)		10.2
Fair value of contingent payment		$ 28,200
OUS Milestone
Business Acquisition [Line Items]
Purchase price of common shares (in shares)	2.7
Contingent consideration liability, lower estimate		10,000
Contingent consideration liability, upper estimate		$ 24,000
OUS Milestone | Common Stock
Business Acquisition [Line Items]
Shares issuable upon milestone achievement, high end (in shares)		6.9
Shares issuable upon milestone achievement, low end (in shares)		1.3
OUS Milestone | Common Stock | Minimum
Business Acquisition [Line Items]
Share price (in USD per share)						$ 3.50
OUS Milestone | Common Stock | Maximum
Business Acquisition [Line Items]
Share price (in USD per share)						$ 7.50
PMA Milestone
Business Acquisition [Line Items]
Value of common shares		$ 15,000
Closing stock price (in USD per share)			$ 5.72
Hypothetical fair value			$ 11,400
PMA Milestone | Maximum
Business Acquisition [Line Items]
Closing stock price (in USD per share)		$ 4.50
Nellix
Business Acquisition [Line Items]
Purchase price of common shares (in shares)		3.2
Value of common shares		$ 19,400