Debt (Tables)

9 Months Ended

Sep. 30, 2017

Debt Disclosure [Abstract]

Schedule of outstanding debt obligations

Our outstanding debt obligations as of September 30, 2017 and December 31, 2016 consisted of the following (in thousands):

	September 30, 2017		December 31, 2016
2023 Senior Notes	$	490,518	$	489,612
2022 Convertible Notes	244,958		—
2019 Convertible Notes	19,941		179,363
2015 Term Loan Facility	—		317,546
Total long-term debt	755,417		986,521
Less: current maturities	—		21,166
Long-term debt, net of current maturities	$	755,417	$	965,355

Schedule of outstanding convertible debt

The outstanding balances of our Convertible Notes as of September 30, 2017 consisted of the following (in thousands):

	2022 Convertible Notes		2019 Convertible Notes		Total
Liability component:
Principal	$	320,000	$	21,417	$	341,417
Less: debt discount and issuance costs, net	75,042		1,476		76,518
Net carrying amount	$	244,958	$	19,941	$	264,899
Equity Component	$	72,576	$	9,905	$	82,481

Schedule of total interest expense recognized related to the convertible notes

The following table sets forth total interest expense recognized related to the Convertible Notes during the three and nine months ended September 30, 2017 and 2016 (in thousands):

	Three Months Ended September 30,				Nine Months Ended September 30,
	2017		2016		2017		2016
Contractual interest expense	$	2,840	$	1,250	$	6,033	$	3,750
Amortization of debt issuance costs	348		273		944		797
Amortization of debt discount	3,264		1,920		7,909		5,602
Total interest expense	$	6,452	$	3,443	$	14,886	$	10,149

Schedule of future annual principal payments on long-term debt

Future annual principal payments on our long-term debt as of September 30, 2017 were as follows (in thousands):

Period	Future Annual Principal Payments
Remainder of Year Ending December 31, 2017	$	—
Year Ending December 31, 2018	—
Year Ending December 31, 2019	21,417
Year Ending December 31, 2020	—
Year Ending December 31, 2021	—
Thereafter	820,000
Total	$	841,417