Convertible Notes and Credit Facilities Convertible Notes and Credit Facilities - Convertible Roll Forward (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Principal amount	$ 128,250
Less: Debt discount, net of amortization	(26,732)
Less: Debt issuance costs, net of amortization	(3,223)
Carrying amount	$ 98,295	$ 0
Remaining amortization period (years)	4 years 10 months 28 days
Effective interest rate on liability component	9.94%
Value of conversion option	$ 26,925
Less: Equity issuance costs	(863)
Carrying amount	$ 26,062