Convertible Senior Notes (Tables)

12 Months Ended

Dec. 31, 2021

Debt Disclosure [Abstract]

Convertible Debt Balances

The Notes consisted of the following balances reported in the Consolidated Balance Sheets as of December 31, 2021 and 2020:

	December 31,
	2021		2020
	(In thousands)
Liability:
Principal amount	$	575,000	$	575,000
Unamortized discount	(77,136)		(95,744)
Unamortized debt issuance costs	(9,712)		(12,055)
Convertible senior notes, liability component (1)	$	488,152	$	467,201
Convertible senior notes, equity component (2)	$	72,732	$	72,732

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(1)    Classified as a current liability as of December 31, 2021 and a long-term liability as of December 30, 2020 in the Consolidated Balance Sheets.

(2)    Included in additional paid-in capital in the Consolidated Balance Sheets.

Summary of the Components of Interest Expense

The following table summarizes the components of interest expense resulting from the Notes recognized in interest and other income (expense), net in the Consolidated Statements of Operations for the years ended December 31, 2021 and 2020:

	Year Ended December 31,
	2021		2020
	(In thousands)
Contractual coupon interest	$	1,438	$	379
Amortization of discount	$	18,608	$	4,766
Amortization of debt issuance costs	$	2,343	$	600