Debt - Schedule of Convertible Notes (Details) - USD ($) $ in Thousands		6 Months Ended
		Jun. 30, 2020	May 31, 2017	Jun. 30, 2015
2017 Convertible Notes [Member]
Debt Instrument [Line Items]
Remaining life in months		47 months
Gross proceeds		$ 289,000	$ 289,000
Less: debt discount, net of amortization		(42,795)
Less: debt issuance cost, net of amortization		(3,318)
Net carrying amount		242,887
Equity component	[1]	$ 70,140
2015 Convertible Notes [Member]
Debt Instrument [Line Items]
Remaining life in months		23 months
Gross proceeds		$ 224,500		$ 224,500
Less: debt discount, net of amortization		(16,934)
Less: debt issuance cost, net of amortization		(1,569)
Net carrying amount		205,997
Equity component	[1]	$ 52,903

[1] Included in Additional paid-in-capital on the consolidated balance sheet as of June 30, 2020.