Debt (Tables)

12 Months Ended

Dec. 31, 2016

Debt Disclosure [Abstract]

Schedule of outstanding debt obligations

Our outstanding debt obligations as of December 31, 2016 and December 31, 2015 consisted of the following (in thousands):

	December 31,
	2016		2015
2023 Senior Notes	$	489,612	$	488,481
2015 Term Loan Facility	317,546		332,688
2.5% Convertible Notes	179,363		170,749
Total long-term debt	986,521		991,918
Less: current maturities	21,166		17,500
Long-term debt, net of current maturities	$	965,355	$	974,418

Schedule of outstanding convertible debt

Our outstanding Convertible Note balances as of December 31, 2016 consisted of the following (in thousands):

	December 31, 2016
Liability component:
Principal	$	199,998
Less: debt discount and issuance costs, net	(20,635		)
Net carrying amount	$	179,363

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 2016, 2015 and 2014 (in thousands):

	Years Ended December 31,
	2016		2015		2014
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

Schedule of maturities of long-term debt

Future Payments

Future annual principal payments on our long-term debt as of December 31, 2016 were as follows (in thousands):

Period	Future Annual Principal Payments
Year Ending December 31, 2017	$	21,166
Year Ending December 31, 2018	17,500
Year Ending December 31, 2019	217,498
Year Ending December 31, 2020	17,500
Year Ending December 31, 2021	254,459
Thereafter	500,000
Total	$	1,028,123