Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Class A common stock	Class B common stock	Class U common stock	Common Stock Class A common stock	Common Stock Class B common stock	Common Stock Class U common stock	Treasury Stock	Additional Paid-in Capital	Accumulated Deficit	Accumulated Other Comprehensive Income (Loss)	Noncontrolling Interest
Balance, Beginning at Dec. 31, 2019	$ 288,172				$ 6	$ 2	$ 1		$ 836,170	$ (547,876)	$ (131)
Balance, Beginning, Shares at Dec. 31, 2019					60,074,698	14,927,613	9,352,729
Issuance of common stock upon exercise of stock options or awards of restricted stock units, Shares	10,000
Tax payments related to shares withheld for share-based compensation plans	$ (1,426)								(1,426)
Tax payments related to shares withheld for share-based compensation plans, shares					944,207
Stock-based compensation expense	5,125								5,125
Repurchase of Class A common stock	(525)	$ (500)							(525)
Repurchase of Class A common stock, Shares		(300,000)			(259,500)			259,500
Retirement of treasury stock, Shares								(259,500)
Dividends paid	(10,531)								(10,531)
Change in fair value of marketable securities	(3)										(3)
Foreign currency translation gain (loss)	(922)										(922)
Net Income Loss Attributable to Common Stockholders	(3,910)									(3,910)
Balance, Ending at Dec. 31, 2020	275,980				$ 6	$ 2	$ 1		828,813	(551,786)	(1,056)
Balance, Ending, Shares at Dec. 31, 2020					60,759,405	14,927,613	9,352,729
Issuance of common stock upon exercise of stock options or awards of restricted stock units	$ 416								416
Issuance of common stock upon exercise of stock options or awards of restricted stock units, Shares	533,000				151,000
Tax payments related to shares withheld for share-based compensation plans	$ (4,729)								(4,729)
Tax payments related to shares withheld for share-based compensation plans, shares					1,406,491
Stock-based compensation expense	9,595								9,595
Class B common stock exchanged for Class A common stock, shares					800,000	(800,000)
Repurchase of Class A common stock, Shares		0
Dividends paid	(8,531)								(8,531)
Change in fair value of marketable securities	(105)										(105)
Foreign currency translation gain (loss)	184										184
Acquisition of redeemable noncontrolling interest	(45,176)								(45,176)
Net Income Loss Attributable to Common Stockholders	29,292									29,292
Balance, Ending at Dec. 31, 2021	256,926				$ 6	$ 2	$ 1		780,388	(522,494)	(977)
Balance, Ending, Shares at Dec. 31, 2021		63,116,896	14,127,613	9,352,729	63,116,896	14,127,613	9,352,729
Issuance of common stock upon exercise of stock options or awards of restricted stock units	$ 219								219
Issuance of common stock upon exercise of stock options or awards of restricted stock units, Shares	91,000				66,000
Tax payments related to shares withheld for share-based compensation plans	$ (4,524)								(4,524)
Tax payments related to shares withheld for share-based compensation plans, shares					2,615,319
Stock-based compensation expense	20,034								20,034
Class B common stock exchanged for Class A common stock					$ 2	$ (2)
Class B common stock exchanged for Class A common stock, shares					14,127,613	(14,127,613)
Repurchase of Class A common stock	(11,280)	$ (11,300)							(11,280)
Repurchase of Class A common stock, Shares		(1,800,000)			(1,753,001)			1,753,001
Retirement of treasury stock, Shares								(1,753,001)
Dividends paid	(8,539)								(8,539)
Change in fair value of marketable securities	(899)										(899)
Foreign currency translation gain (loss)	(45)										(45)
OCI release due to realized gain (loss) on marketable securities	411										411
Acquisition of noncontrolling interest	12,897											$ 12,897
Net Income Loss Attributable to Common Stockholders	20,169									18,119		2,050
Balance, Ending at Dec. 31, 2022	$ 285,369				$ 8		$ 1		$ 776,298	$ (504,375)	$ (1,510)	$ 14,947
Balance, Ending, Shares at Dec. 31, 2022		78,172,827	0	9,352,729	78,172,827		9,352,729