CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Treasury Stock	Accumulated Other Comprehensive Income	Retained Earnings	Noncontrolling Interests
Balance, Stockholders Equity at Dec. 31, 2019	$ 641,513	$ 37	$ 645,256	$ (251,241)	$ 15	$ 246,383	$ 1,063
Balance (in shares) at Dec. 31, 2019		36,638,021
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of stock - employee stock purchase plan	3,562		3,562
Issuance of stock - employee stock purchase plan (shares)		21,561
Issuance of stock - 401 (k) plan	3,057		3,057
Issuance of stock - 401 (k) plan (shares)		18,312
Issuance/(cancellation) of non-vested stock	0		0
Issuance/(cancellation) of non-vested stock (shares)		169,489
Exercise of stock options	6,325	$ 1	6,324
Exercise of stock options (in shares)		622,829
Non-cash compensation	26,730		26,730
Surrendered shares	(54,493)		13,358	(67,851)
Noncontrolling interest distributions	(1,122)						(1,122)
Write-off of other comprehensive income	(15)				(15)
Net income	185,184					183,608	1,576
Balance, Stockholders Equity at Dec. 31, 2020	810,741	$ 38	698,287	(319,092)	0	429,991	1,517
Balance (in shares) at Dec. 31, 2020		37,470,212
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of stock - employee stock purchase plan	3,968		3,968
Issuance of stock - employee stock purchase plan (shares)		20,823
Issuance/(cancellation) of non-vested stock	0		0
Issuance/(cancellation) of non-vested stock (shares)		151,365
Exercise of stock options	2,054		2,054
Exercise of stock options (in shares)		32,468
Non-cash compensation	23,809		23,809
Surrendered shares	(16,898)			(16,898)
Shares repurchased	(99,878)			(99,878)
Noncontrolling interest contributions	250						250
Noncontrolling interest distributions	(1,747)						(1,747)
Acquired noncontrolling interest	43,858						43,858
Net income	210,166					209,072	1,094
Balance, Stockholders Equity at Dec. 31, 2021	976,323	$ 38	728,118	(435,868)	0	639,063	44,972
Balance (in shares) at Dec. 31, 2021		37,674,868
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of stock - employee stock purchase plan	3,848		3,848
Issuance of stock - employee stock purchase plan (shares)		36,206
Issuance/(cancellation) of non-vested stock	0		0
Issuance/(cancellation) of non-vested stock (shares)		142,477
Exercise of stock options	$ 2,304		2,304
Exercise of stock options (in shares)	37,635	37,635
Non-cash compensation	$ 16,560		16,560
Surrendered shares	(7,981)			(7,981)
Shares repurchased	(17,351)			(17,351)
Noncontrolling interest contributions	12,401						12,401
Noncontrolling interest distributions	(1,561)						(1,561)
Sale of noncontrolling interest	4,331		4,233				98
Net income	117,699					118,609	(910)
Balance, Stockholders Equity at Dec. 31, 2022	$ 1,106,573	$ 38	$ 755,063	$ (461,200)	$ 0	$ 757,672	$ 55,000
Balance (in shares) at Dec. 31, 2022		37,891,186