Debt (Tables)

12 Months Ended

Dec. 31, 2021

Debt Disclosure [Abstract]

Summary of Long-term Debt

Long-term debt as of December 31, 2021 and 2020 consists of the following (in thousands):

	2021		2020
4.625% Senior Notes	$	641,276	$	750,000
Convertible Notes:
3.25% Convertible Notes	—		402,414
1.75% Convertible Notes	550,000		550,000
Total Notes	1,191,276		1,702,414
Paycheck Protection Program Loan	—		910
Less: Unamortized discount	(91,593)		(112,798)
Deferred issuance costs	(9,056)		(11,505)
Total debt	1,090,627		1,579,021
Less: current portion	(54,609)		(396,801)
Total long-term debt, less current portion	$	1,036,018	$	1,182,220

Future Principal Payments for Debt

At December 31, 2021, future principal payments for debt are as follows (in thousands):

Years Ended December 31,
2022	$	54,609
2023	—
2024	—
2025	—
2026	—
Thereafter	1,136,667
	$	1,191,276

Additional Information Related to Senior Notes

The following table provides additional information on the 4.625% Senior Notes (in thousands):

	2021
Principal amount of 4.625% Senior Notes	$	641,276
Less: Unamortized discount	(4,259)
Less: Debt issuance costs	(1,339)
Net carrying amount of 4.625% Senior Notes	$	635,678

Additional Information Related to Convertible Notes

The following table provides additional information related to the 3.25% Convertible Notes (in thousands):

	2021		2020
Additional paid-in capital	$	—	$	37,688
Principal amount of 3.25% Convertible Notes	$	—	$	402,414
Less: Unamortized discount of the liability component	—		(4,644)
Less: Carrying amount of debt issuance costs	—		(855)
Net carrying amount of 3.25% Convertible Notes	$	—	$	396,915

The following table provides additional information related to the 1.75% Convertible Notes (in thousands):

	2021		2020
Additional paid-in capital	$	88,138	$	88,138
Principal amount of 1.75% Convertible Notes	$	550,000	$	550,000
Less: Unamortized discount of the liability component	(87,334)		(102,631)
Less: Carrying amount of debt issuance costs	(7,717)		(8,889)
Net carrying amount of 1.75% Convertible Notes	$	454,949	$	438,480

Components of Interest Expense Related to Convertible Notes

The following table provides the components of interest expense related to the 3.25% Convertible Notes (in thousands):

	2021		2020		2019
Cash interest expense (coupon interest expense)	$	5,994	$	13,080	$	13,081
Non-cash amortization of discount on 3.25% Convertible Notes	4,645		9,717		9,171
Amortization of debt issuance costs	855		1,749		1,600
Total interest expense related to 3.25% Convertible Notes	$	11,494	$	24,546	$	23,852

The following table provides the components of interest expense related to the 1.75% Convertible Notes (in thousands):

	2021		2020
Cash interest expense (coupon interest expense)	$	9,625	$	9,653
Non-cash amortization of discount on 1.75% Convertible Notes	15,338		14,563
Amortization of debt issuance costs	1,173		1,098
Total interest expense related to 1.75% Convertible Notes	$	26,136	$	25,314