Condensed Consolidated Statement of Stockholders' Equity - USD ($) $ in Thousands	Total	COMMON STOCK, AMOUNT	Additional Paid-in Capital	AOCI Attributable to Parent	Treasury Stock	Retained Earnings	Parent	Noncontrolling Interest
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest, Beginning Balance at Dec. 31, 2019	$ 459,712	$ 18,625	$ 122,717	$ 1,212	$ (69,724)	$ 386,864	$ 459,694	$ 18
Net Income (Loss), Including Portion Attributable to Nonredeemable Noncontrolling Interest	4,733					4,699	4,699	34
Other Comprehensive Income (Loss), Net of Tax	1,642			1,642			1,642	0
Dividends, Common Stock, Cash	3,246					3,246	3,246	0
Sharebased Compensation Effect On Stockholders Equity	1,087		1,087				1,087	0
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest, Ending Balance at Jun. 30, 2020	459,324	18,625	123,804	2,854	(74,325)	388,317	459,275	49
Treasury Stock, Value, Acquired, Cost Method	4,601				4,601		4,601	0
Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders	3						0	3
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest, Beginning Balance at Mar. 31, 2020	459,898	18,625	123,260	1,101	(71,196)	388,102	459,892	6
Net Income (Loss), Including Portion Attributable to Nonredeemable Noncontrolling Interest	464					421	421	43
Other Comprehensive Income (Loss), Net of Tax	1,753			1,753			1,753	0
Dividends, Common Stock, Cash	206					206	206	0
Sharebased Compensation Effect On Stockholders Equity	544		544				544	0
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest, Ending Balance at Jun. 30, 2020	459,324	18,625	123,804	2,854	(74,325)	388,317	459,275	49
Treasury Stock, Value, Acquired, Cost Method	3,129				3,129		3,129	0
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest, Beginning Balance at Dec. 31, 2020	469,806	18,625	124,757	4,197	(77,088)	399,273	469,764	42
Net Income (Loss), Including Portion Attributable to Nonredeemable Noncontrolling Interest	82,090					82,092	82,092	(2)
Other Comprehensive Income (Loss), Net of Tax	(977)			(977)			(977)	0
Dividends, Common Stock, Cash	3,226					3,226	3,226	0
Sharebased Compensation Effect On Stockholders Equity	935		896		39		935	0
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest, Ending Balance at Jun. 30, 2021	548,488	18,625	125,653	3,220	(77,189)	478,139	548,448	40
Treasury Stock, Value, Acquired, Cost Method	140				140		140	0
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest, Beginning Balance at Mar. 31, 2021	473,789	18,625	125,189	2,268	(77,228)	404,894	473,748	41
Net Income (Loss), Including Portion Attributable to Nonredeemable Noncontrolling Interest	76,470					76,471	76,471	(1)
Other Comprehensive Income (Loss), Net of Tax	952			952			952	0
Dividends, Common Stock, Cash	3,226					3,226	3,226	0
Sharebased Compensation Effect On Stockholders Equity	503		464		39		503	0
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest, Ending Balance at Jun. 30, 2021	$ 548,488	$ 18,625	$ 125,653	$ 3,220	$ (77,189)	$ 478,139	$ 548,448	$ 40