Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock	Additional paid-in capital	Accumulated other comprehensive loss	Accumulated deficit
Beginning balance (in shares) at Dec. 31, 2020		272,154,504
Beginning balance at Dec. 31, 2020	$ 341,599	$ 2,722	$ 741,113	$ (26,233)	$ (376,003)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	102,633				102,633
Other comprehensive income (loss)	(28,653)			(28,653)
Purchase of capped call options, net of tax	(39,021)		(39,021)
Dividends declared	(16,591)				(16,591)
Shares issued in connection with deferred compensation plan, net (in shares)		2,202,079
Shares issued in connection with deferred compensation plan, net	(61,912)	$ 22			(61,934)
Deferred compensation plan elective participant deferrals	1,493		1,493
Shares issued in connection with Executive Bonus Plan, net (in shares)		149,447
Shares issued in connection with Executive Bonus Plan, net	7,007	$ 2	11,721		(4,716)
Stock option exercises, net (in shares)		3,657,058
Stock option exercises, net	(24,703)	$ 36	4,288		(29,027)
Acquisition option exercises, net (in shares)		3,141,342
Acquisition option exercises, net	182,390	$ 31	182,359
Shares issued for stock grants, net (in shares)		7,824
Shares issued for stock grants, net	450		450
Stock-based compensation expense	8,548		8,548
Shares related to restricted stock, net (in shares)		(123,127)
Shares related to restricted stock, net	(709)	$ (1)			(708)
Ending balance (in shares) at Jun. 30, 2021		281,189,127
Ending balance at Jun. 30, 2021	472,531	$ 2,812	910,951	(54,886)	(386,346)
Beginning balance (in shares) at Mar. 31, 2021		273,722,483
Beginning balance at Mar. 31, 2021	353,997	$ 2,737	732,635	(35,394)	(345,981)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	45,627				45,627
Other comprehensive income (loss)	(19,492)			(19,492)
Purchase of capped call options, net of tax	(19,591)		(19,591)
Dividends declared	(8,372)				(8,372)
Shares issued in connection with deferred compensation plan, net (in shares)		1,862,576
Shares issued in connection with deferred compensation plan, net	(53,053)	$ 19			(53,072)
Deferred compensation plan elective participant deferrals	639		639
Shares issued in connection with Executive Bonus Plan, net (in shares)		69,486
Shares issued in connection with Executive Bonus Plan, net	3,470	$ 1	6,148		(2,679)
Stock option exercises, net (in shares)		2,393,937
Stock option exercises, net	(19,296)	$ 24	2,549		(21,869)
Acquisition option exercises, net (in shares)		3,141,342
Acquisition option exercises, net	182,390	$ 31	182,359
Shares issued for stock grants, net (in shares)		7,824
Shares issued for stock grants, net	450		450
Stock-based compensation expense	5,762		5,762
Shares related to restricted stock, net (in shares)		(8,521)
Shares related to restricted stock, net	0
Ending balance (in shares) at Jun. 30, 2021		281,189,127
Ending balance at Jun. 30, 2021	472,531	$ 2,812	910,951	(54,886)	(386,346)
Beginning balance (in shares) at Dec. 31, 2021		282,526,719
Beginning balance at Dec. 31, 2021	409,222	$ 2,825	937,805	(91,774)	(439,634)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	112,061				112,061
Other comprehensive income (loss)	2,643			2,643
Dividends declared	(17,031)				(17,031)
Shares issued in connection with deferred compensation plan, net (in shares)		3,425,795
Shares issued in connection with deferred compensation plan, net	(24,246)	$ 34	(26)		(24,254)
Deferred compensation plan elective participant deferrals	3,108		3,108
Shares issued in connection with Executive Bonus Plan, net (in shares)		159,797
Shares issued in connection with Executive Bonus Plan, net	6,696	$ 2	11,891		(5,197)
Shares issued in connection with employee stock purchase plan (in shares)		109,749
Shares issued in connection with employee stock purchase plan	$ 4,490	$ 1	4,610		(121)
Stock option exercises, net (in shares)	900,000	2,054,585
Stock option exercises, net	$ (2,539)	$ 21	5,840		(8,400)
Acquisition option exercises, net (in shares)		185,178
Acquisition option exercises, net	0	$ 2	(2)
Shares issued for stock grants, net (in shares)		13,632
Shares issued for stock grants, net	450		450
Stock-based compensation expense	17,529		17,529
Shares related to restricted stock, net (in shares)		141,705
Shares related to restricted stock, net	(2,148)	$ 2	(2)		(2,148)
Repurchase of Class B Common Stock under approved program (in shares)		(463,001)
Repurchase of Class B Common Stock under approved program	(13,242)	$ (5)			(13,237)
Ending balance (in shares) at Jun. 30, 2022		288,154,159
Ending balance at Jun. 30, 2022	496,993	$ 2,882	981,203	(89,131)	(397,961)
Beginning balance (in shares) at Mar. 31, 2022		285,134,093
Beginning balance at Mar. 31, 2022	457,653	$ 2,851	957,498	(75,324)	(427,372)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	55,673				55,673
Other comprehensive income (loss)	(13,807)			(13,807)
Dividends declared	(8,678)				(8,678)
Shares issued in connection with deferred compensation plan, net (in shares)		2,616,044
Shares issued in connection with deferred compensation plan, net	0	$ 26	(26)
Deferred compensation plan elective participant deferrals	2,439		2,439
Shares issued in connection with Executive Bonus Plan, net (in shares)		87,692
Shares issued in connection with Executive Bonus Plan, net	3,892	$ 1	6,896		(3,005)
Stock option exercises, net (in shares)		653,336
Stock option exercises, net	2,344	$ 7	3,086		(749)
Acquisition option exercises, net (in shares)		35,323
Acquisition option exercises, net	0	$ 1	(1)
Shares issued for stock grants, net (in shares)		13,632
Shares issued for stock grants, net	450		450
Stock-based compensation expense	10,862		10,862
Shares related to restricted stock, net (in shares)		77,040
Shares related to restricted stock, net	(593)	$ 1	(1)		(593)
Repurchase of Class B Common Stock under approved program (in shares)		(463,001)
Repurchase of Class B Common Stock under approved program	(13,242)	$ (5)			(13,237)
Ending balance (in shares) at Jun. 30, 2022		288,154,159
Ending balance at Jun. 30, 2022	$ 496,993	$ 2,882	$ 981,203	$ (89,131)	$ (397,961)