Debt - Schedule of Total Interest Expense Recognized Related to the Convertible Notes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Amortization of debt discount	$ 0	$ (12,491)	$ 0
Total interest expense	73,153	53,251	14,697
Convertible Notes
Debt Instrument [Line Items]
Contractual interest expense	5,000	5,000	4,375
Amortization of debt issuance costs	1,072	985	800
Amortization of debt discount	7,544	6,927	5,629
Total interest expense	$ 13,616	$ 12,912	$ 10,804