UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) shares in Thousands, $ in Thousands	Total	Cumulative Effect, Period of Adoption, Adjustment	Common Stock	Additional Paid-In Capital	Additional Paid-In Capital Cumulative Effect, Period of Adoption, Adjustment	Retained Earnings	Retained Earnings Cumulative Effect, Period of Adoption, Adjustment	Accumulated Other Comprehensive (Loss)
Balance, beginning of period (in shares) at Dec. 31, 2019			79,599
Balance, beginning of period at Dec. 31, 2019	$ 539,010		$ 796	$ 140,523		$ 410,919		$ (13,228)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Equity component of convertible senior notes, net	61,604			61,604
Repurchase of common stock (in shares)			(87)
Repurchase of common stock	(6,000)		$ (1)	(5,999)
Issuance of common stock for share-based compensation plans (in shares)			564
Issuance of common stock for stock compensation plans	(23,011)		$ 6	(23,017)
Stock-based compensation	23,199			23,199
Cash dividends declared ($0.03 per share)	(2,405)					(2,405)
Other comprehensive income (loss)	(414)							(414)
Net income (loss)	(25,372)					(25,372)
Balance, end of period (in shares) at Mar. 31, 2020			80,076
Balance, end of period at Mar. 31, 2020	566,611		$ 801	196,310		383,142		(13,642)
Balance, beginning of period (in shares) at Dec. 31, 2019			79,599
Balance, beginning of period at Dec. 31, 2019	539,010		$ 796	140,523		410,919		(13,228)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Other comprehensive income (loss)	1,614
Net income (loss)	(46,112)
Balance, end of period (in shares) at Jun. 30, 2020			80,420
Balance, end of period at Jun. 30, 2020	556,282		$ 804	207,103		359,989		(11,614)
Balance, beginning of period (in shares) at Dec. 31, 2019			79,599
Balance, beginning of period at Dec. 31, 2019	$ 539,010		$ 796	140,523		410,919		(13,228)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Accounting standards update	Accounting Standards Update 2020-06
Balance, end of period (in shares) at Dec. 31, 2020	80,890		80,890
Balance, end of period at Dec. 31, 2020	$ 542,172	$ (52,205)	$ 809	204,432	$ (61,604)	339,879	$ 9,399	(2,948)
Balance, beginning of period (in shares) at Mar. 31, 2020			80,076
Balance, beginning of period at Mar. 31, 2020	566,611		$ 801	196,310		383,142		(13,642)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Repurchase of common stock (in shares)			(23)
Repurchase of common stock	(2,199)			(2,199)
Issuance of common stock for share-based compensation plans (in shares)			349
Issuance of common stock for stock compensation plans	(14,082)		$ 3	(14,085)
Issuance of common stock under the employee stock purchase plan (in shares)			18
Issuance of common stock under the employee stock purchase plan	1,403			1,403
Stock-based compensation	25,674			25,674
Cash dividends declared ($0.03 per share)	(2,413)					(2,413)
Other comprehensive income (loss)	2,028							2,028
Net income (loss)	(20,740)					(20,740)
Balance, end of period (in shares) at Jun. 30, 2020			80,420
Balance, end of period at Jun. 30, 2020	$ 556,282		$ 804	207,103		359,989		(11,614)
Balance, beginning of period (in shares) at Dec. 31, 2020	80,890		80,890
Balance, beginning of period at Dec. 31, 2020	$ 542,172	(52,205)	$ 809	204,432	(61,604)	339,879	9,399	(2,948)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Repurchase of common stock (in shares)			(70)
Repurchase of common stock	(9,146)		$ (1)	(9,145)
Issuance of common stock for share-based compensation plans (in shares)			402
Issuance of common stock for stock compensation plans	(25,509)		$ 4	(25,513)
Issuance of common stock under the employee stock purchase plan (in shares)			24
Issuance of common stock under the employee stock purchase plan	2,288			2,288
Stock-based compensation	30,100			30,100
Cash dividends declared ($0.03 per share)	(2,438)					(2,438)
Other comprehensive income (loss)	280							280
Net income (loss)	(6,617)					(6,617)
Balance, end of period (in shares) at Mar. 31, 2021			81,246
Balance, end of period at Mar. 31, 2021	$ 478,925		$ 812	140,558		340,223		(2,668)
Balance, beginning of period (in shares) at Dec. 31, 2020	80,890		80,890
Balance, beginning of period at Dec. 31, 2020	$ 542,172	$ (52,205)	$ 809	204,432	$ (61,604)	339,879	$ 9,399	(2,948)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Other comprehensive income (loss)	1,862
Net income (loss)	$ 30,674
Balance, end of period (in shares) at Jun. 30, 2021	81,456		81,456
Balance, end of period at Jun. 30, 2021	$ 522,468		$ 815	147,670		375,069		(1,086)
Balance, beginning of period (in shares) at Mar. 31, 2021			81,246
Balance, beginning of period at Mar. 31, 2021	478,925		$ 812	140,558		340,223		(2,668)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Repurchase of common stock (in shares)			(81)
Repurchase of common stock	(10,246)		$ (1)	(10,245)
Issuance of common stock for share-based compensation plans (in shares)			267
Issuance of common stock for stock compensation plans	(16,196)		$ 3	(16,199)
Issuance of common stock under the employee stock purchase plan (in shares)			24
Issuance of common stock under the employee stock purchase plan	2,859		$ 1	2,858
Stock-based compensation	30,698			30,698
Cash dividends declared ($0.03 per share)	(2,445)					(2,445)
Other comprehensive income (loss)	1,582							1,582
Net income (loss)	$ 37,291					37,291
Balance, end of period (in shares) at Jun. 30, 2021	81,456		81,456
Balance, end of period at Jun. 30, 2021	$ 522,468		$ 815	$ 147,670		$ 375,069		$ (1,086)