UNAUDITED CONSOLIDATED STATEMENT OF CHANGES IN EQUITY - USD ($) $ in Thousands	Total	Common Class A	Common Class B	Additional Paid-In Capital	Accumulated Other Comprehensive Income (Loss)	Retained Earnings	Non-Controlling Interests
Beginning Balance at Dec. 31, 2019	$ 108,210	$ 179		$ 4,829	$ (3)	$ 26,439	$ 76,766
Beginning Balance (in shares) at Dec. 31, 2019		18,009,350	52,879,323
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Amortization of Non-Cash Compensation	2,052			479			1,573
Amortization of Non-Cash Compensation (in shares)		10,000	321,949
Issuance of Shares under Equity Incentive Plan	3,842			890			2,952
Issuance of Shares under Equity Incentive Plan (in shares)			637,349
Sale of Shares under Equity Incentive Plan	1,902			436			1,466
Sale of Shares under Equity Incentive Plan (in shares)			430,955
Directors' Share Grants	331			76			255
Net Income	769						769
Foreign Currency Translation Adjustments	(505)				122		(627)
Repurchase and Retirement of Class A Common Stock	(5,648)	$ (8)		(1,283)			(4,357)
Repurchase and Retirement Shares/Units (in shares)		(823,792)	(94,830)
Repurchase and Retirement of Class B Units	(565)			(131)			(434)
Class A Cash Dividends Declared and Paid	(8,172)					(8,172)
Tax Impact of Transactions with Non-Controlling Shareholders	(717)			(717)
Effect of Deconsolidation	(1,685)						(1,685)
Contributions from Non-Controlling Interests	641						641
Distributions to Non-Controlling Interests	(33,327)						(33,327)
Other				(1,224)			1,224
Ending Balance at Mar. 31, 2020	67,128	$ 171		3,355	119	18,267	45,216
Ending Balance (in shares) at Mar. 31, 2020		17,195,558	54,174,746
Beginning Balance at Dec. 31, 2019	108,210	$ 179		4,829	(3)	26,439	76,766
Beginning Balance (in shares) at Dec. 31, 2019		18,009,350	52,879,323
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Sale of Shares under Equity Incentive Plan (in shares)			527,555
Net Income	$ 13,618
Options Exercised (in shares)	0
Repurchase and Retirement Shares/Units (in shares)		(1,090,030)	(94,830)
Ending Balance at Jun. 30, 2020	$ 78,624	$ 169		3,500	(50)	19,948	55,057
Ending Balance (in shares) at Jun. 30, 2020		16,946,126	54,254,540
Beginning Balance at Mar. 31, 2020	67,128	$ 171		3,355	119	18,267	45,216
Beginning Balance (in shares) at Mar. 31, 2020		17,195,558	54,174,746
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Amortization of Non-Cash Compensation	2,015			449			1,566
Sale of Shares under Equity Incentive Plan	291			65			226
Sale of Shares under Equity Incentive Plan (in shares)			96,600
Modification, shares		16,806	(16,806)
Directors' Share Grants	(106)			(23)			(83)
Net Income	12,849					2,198	10,651
Foreign Currency Translation Adjustments	$ 283				(169)		452
Options Exercised (in shares)	0
Repurchase and Retirement of Class A Common Stock	$ (1,396)	$ (2)		(288)			(1,106)
Repurchase and Retirement Shares/Units (in shares)		(266,238)
Class A Cash Dividends Declared and Paid	(517)					(517)
Tax Impact of Transactions with Non-Controlling Shareholders	(92)			(92)
Contributions from Non-Controlling Interests	68						68
Distributions to Non-Controlling Interests	(1,899)						(1,899)
Other				34			(34)
Ending Balance at Jun. 30, 2020	78,624	$ 169		3,500	(50)	19,948	55,057
Ending Balance (in shares) at Jun. 30, 2020		16,946,126	54,254,540
Beginning Balance at Dec. 31, 2020	108,955	$ 173		5,190	132	25,611	77,849
Beginning Balance (in shares) at Dec. 31, 2020		17,328,899	54,313,620
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Amortization of Non-Cash Compensation	2,145			462			1,683
Amortization of Non-Cash Compensation (in shares)		14,201	320,495
Issuance of Shares under Equity Incentive Plan	3,822			872			2,950
Issuance of Shares under Equity Incentive Plan (in shares)		12,353	805,987
Sale of Shares under Equity Incentive Plan	167			36			131
Sale of Shares under Equity Incentive Plan (in shares)			26,097
Directors' Share Grants	247			53			194
Directors' Share Grants (in shares)		12,338
Net Income	25,029					4,187	20,842
Foreign Currency Translation Adjustments	(12)				(5)		(7)
Repurchase and Retirement of Class A Common Stock	(2,390)	$ (3)		(516)			(1,871)
Repurchase and Retirement Shares/Units (in shares)		(275,218)	(18,476)
Repurchase and Retirement of Class B Units	(90)			(20)			(70)
Class A Cash Dividends Declared and Paid	(4,302)					(4,302)
Tax Impact of Transactions with Non-Controlling Shareholders	(494)			(494)
Contributions from Non-Controlling Interests	303						303
Distributions to Non-Controlling Interests	(29,725)						(29,725)
Other				(541)			541
Ending Balance at Mar. 31, 2021	103,655	$ 170		5,042	127	25,496	72,820
Ending Balance (in shares) at Mar. 31, 2021		17,092,573	55,447,723
Beginning Balance at Dec. 31, 2020	108,955	$ 173		5,190	132	25,611	77,849
Beginning Balance (in shares) at Dec. 31, 2020		17,328,899	54,313,620
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Unit Conversion	265
Sale of Shares under Equity Incentive Plan (in shares)			33,979
Net Income	$ 52,106
Options Exercised (in shares)	11,051
Repurchase and Retirement Shares/Units (in shares)		(372,874)	(21,266)
Ending Balance at Jun. 30, 2021	$ 131,469	$ 177		5,633	114	29,586	95,959
Ending Balance (in shares) at Jun. 30, 2021		17,756,185	54,699,280
Beginning Balance at Mar. 31, 2021	103,655	$ 170		5,042	127	25,496	72,820
Beginning Balance (in shares) at Mar. 31, 2021		17,092,573	55,447,723
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Unit Conversion	265	$ 8		1,326			(1,069)
Unit Conversion (in shares)		760,000	(760,000)
Amortization of Non-Cash Compensation	2,215			479			1,736
Sale of Shares under Equity Incentive Plan	55			12			43
Sale of Shares under Equity Incentive Plan (in shares)			7,882
Directors' Share Grants	139			30			109
Directors' Share Grants (in shares)		1,268
Net Income	27,077					4,603	22,474
Foreign Currency Translation Adjustments	$ (117)				(13)		(104)
Options Exercised (in shares)	11,051		6,465
Repurchase and Retirement of Class A Common Stock	$ (1,047)	$ (1)		(227)			(819)
Repurchase and Retirement Shares/Units (in shares)		(97,656)	(2,790)
Repurchase and Retirement of Class B Units	(32)			(7)			(25)
Class A Cash Dividends Declared and Paid	(513)					(513)
Tax Impact of Transactions with Non-Controlling Shareholders	(132)			(132)
Contributions from Non-Controlling Interests	13,835						13,835
Distributions to Non-Controlling Interests	(13,931)						(13,931)
Other				(890)			890
Ending Balance at Jun. 30, 2021	$ 131,469	$ 177		$ 5,633	$ 114	$ 29,586	$ 95,959
Ending Balance (in shares) at Jun. 30, 2021		17,756,185	54,699,280