CONSOLIDATED STATEMENT OF STOCKHOLDERS' EQUITY (Unaudited) - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock [Member]	Additional Paid-In Capital [Member]	Treasury Stock [Member]	Retained Earnings [Member]
Balance at Dec. 31, 2020	$ 44,132	$ 555	$ 95,528	$ (626,984)	$ 575,033
Balance (shares) at Dec. 31, 2020		55,489
Purchase of treasury stock, at cost	(49,770)	$ 0	0	49,770	0
Issuance of equity-based incentive awards and dividend equivalents	0	0	(25,112)	26,449	(1,337)
Stock-based compensation expense	35,965	0	33,266	2,699	0
Other	2,278	0	1,234	1,044	0
Dividends paid	(50,198)	0	0	0	(50,198)
Unrealized gain (loss) on marketable securities, net of tax	(13)	0	0	0	(13)
Net income	114,372	0	0	0	114,372
Balance at Sep. 30, 2021	97,006	$ 555	104,587	(645,993)	637,857
Balance (shares) at Sep. 30, 2021		55,489
Stock Issued During Period, Value, Stock Options Exercised	240	$ 0	329	569	0
Balance at Jun. 30, 2021	87,262	$ 555	94,396	(635,627)	627,938
Balance (shares) at Jun. 30, 2021		55,489
Purchase of treasury stock, at cost	(11,234)	$ 0	0	11,234	0
Issuance of equity-based incentive awards and dividend equivalents	0	0	(27)	28	(1)
Stock-based compensation expense	10,362	0	9,827	535	0
Other	696	0	391	305	0
Dividends paid	(17,369)	0	0	0	(17,369)
Unrealized gain (loss) on marketable securities, net of tax	(7)	0	0	0	(7)
Net income	27,296	0	0	0	27,296
Balance at Sep. 30, 2021	97,006	$ 555	104,587	(645,993)	637,857
Balance (shares) at Sep. 30, 2021		55,489
Balance at Dec. 31, 2021	(1,774)	$ 555	109,179	(665,089)	553,581
Balance (shares) at Dec. 31, 2021		55,489
Purchase of treasury stock, at cost	(63,420)	$ 0	0	63,420	0
Issuance of equity-based incentive awards and dividend equivalents	0	0	(9,285)	10,443	(1,158)
Stock-based compensation expense	38,818	0	37,866	952	0
Other	2,678	0	1,610	1,068	0
Dividends paid	(56,866)	0	0	0	(56,866)
Unrealized gain (loss) on marketable securities, net of tax	(85)	0	0	0	(85)
Net income	141,152	0	0	0	141,152
Balance at Sep. 30, 2022	60,503	$ 555	139,370	(716,046)	636,624
Balance (shares) at Sep. 30, 2022		55,489
Balance at Jun. 30, 2022	35,132	$ 555	125,622	(709,810)	618,765
Balance (shares) at Jun. 30, 2022		55,489
Purchase of treasury stock, at cost	(6,615)	$ 0	0	6,615	0
Issuance of equity-based incentive awards and dividend equivalents	0	0	(37)	44	(7)
Stock-based compensation expense	13,341	0	13,339	2	0
Other	779	0	446	333	0
Dividends paid	(19,769)	0	0	0	(19,769)
Unrealized gain (loss) on marketable securities, net of tax	(34)	0	0	0	(34)
Net income	37,669	0	0	0	37,669
Balance at Sep. 30, 2022	$ 60,503	$ 555	$ 139,370	$ (716,046)	$ 636,624
Balance (shares) at Sep. 30, 2022		55,489