Condensed Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($) shares in Thousands, $ in Thousands	Common Stock Including Additional Paid in Capital [Member]	Retained Earnings [Member]	AOCI Attributable to Parent [Member]	Total
Balance (in shares) at Dec. 31, 2020	45,267
Balance at Dec. 31, 2020	$ 657,701	$ 298,746	$ 10,140	$ 966,587
Net income	0	45,413	0	45,413
Other comprehensive loss	0	0	(3,128)	(3,128)
Dividends and dividend equivalents declared	$ 0	(28,953)	0	(28,953)
Common stock issued under the employee equity incentive plan (in shares)	460
Common stock issued under the employee equity incentive plan	$ 10,744	0	0	10,744
Common stock issued under the employee stock purchase plan (in shares)	10
Common stock issued under the employee stock purchase plan	$ 2,293	0	0	2,293
Stock-based compensation expense	28,621	0	0	28,621
Other comprehensive loss	$ 0	0	(3,128)	(3,128)
Balance (in shares) at Mar. 31, 2021	45,737
Balance at Mar. 31, 2021	$ 699,359	315,206	7,012	$ 1,021,577
Balance (in shares) at Dec. 31, 2021	46,256			46,256
Balance at Dec. 31, 2021	$ 803,226	424,879	15,880	$ 1,243,985
Net income	0	79,566	0	79,566
Other comprehensive loss	0	0	(5,578)	(5,578)
Dividends and dividend equivalents declared	$ 0	(36,601)	0	(36,601)
Common stock issued under the employee equity incentive plan (in shares)	362
Common stock issued under the employee equity incentive plan	$ 2,318	0	0	2,318
Common stock issued under the employee stock purchase plan (in shares)	7
Common stock issued under the employee stock purchase plan	$ 2,786	0	0	2,786
Stock-based compensation expense	39,636	0	0	39,636
Other comprehensive loss	$ 0	0	(5,578)	$ (5,578)
Balance (in shares) at Mar. 31, 2022	46,625			46,625
Balance at Mar. 31, 2022	$ 847,966	$ 467,844	$ 10,302	$ 1,326,112