CONSOLIDATED STATEMENTS OF EQUITY - USD ($) $ in Thousands	Total	Common  Stock	Additional paid-in capital	Accumulated other comprehensive (loss) income	Retained Earnings	Treasury stock	Noncontrolling interests
Beginning balance at Dec. 31, 2020	$ 1,012,406	$ 27,080	$ 274,857	$ 17,022	$ 688,819	$ (2,666)	$ 7,294
Increase (Decrease) in Stockholders' Equity
Net income	323,216				323,216
Dividends on Common Stock	(37,235)				(37,235)
Stock-based compensation	11,966	144	11,822
Stock option and employee stock purchase plan exercises	2,715	64	2,651
Stock repurchases	(2,252)	(42)	(2,210)
Purchase of remaining interest of consolidated subsidiary	(5,616)		(4,744)				(872)
Change in net unrealized gains and losses on investments, net of taxes	(13,650)			(13,650)
Reclassification adjustment for realized gains and losses on investments, net of taxes	(2,440)			(2,440)
Foreign currency translation adjustments (net of tax)	(679)			(679)
Net income attributable to noncontrolling interests	16,766						16,766
Distributions to noncontrolling interests	(16,407)						(16,407)
Net effect of changes in ownership and other	5,945						5,945
Ending balance at Dec. 31, 2021	1,294,735	27,246	282,376	253	974,800	(2,666)	12,726
Increase (Decrease) in Stockholders' Equity
Net income	162,305				162,305
Dividends on Common Stock	(45,289)				(45,289)
Stock-based compensation	12,282	164	12,118
Stock option and employee stock purchase plan exercises	5,828	124	5,704
Stock repurchases	(3,262)	(51)	(3,211)
Purchase of remaining interest of consolidated subsidiary	(3,838)		(126)				(3,712)
Change in net unrealized gains and losses on investments, net of taxes	(35,416)			(35,416)
Reclassification adjustment for realized gains and losses on investments, net of taxes	(1,241)			(1,241)
Foreign currency translation adjustments (net of tax)	(14,939)			(14,939)
Net income attributable to noncontrolling interests	19,483						19,483
Distributions to noncontrolling interests	(20,640)						(20,640)
Net effect of changes in ownership and other	257						257
Ending balance at Dec. 31, 2022	1,370,265	27,483	296,861	(51,343)	1,091,816	(2,666)	8,114
Increase (Decrease) in Stockholders' Equity
Net income	30,439				30,439
Dividends on Common Stock	(51,414)				(51,414)
Stock-based compensation	10,920	150	10,770
Stock option and employee stock purchase plan exercises	4,970	132	4,838
Stock repurchases	(1,783)	(42)	(1,741)
Change in net unrealized gains and losses on investments, net of taxes	10,461			10,461
Reclassification adjustment for realized gains and losses on investments, net of taxes	390			390
Foreign currency translation adjustments (net of tax)	5,277			5,277
Net income attributable to noncontrolling interests	15,159						15,159
Distributions to noncontrolling interests	(16,135)						(16,135)
Ending balance at Dec. 31, 2023	$ 1,378,549	$ 27,723	$ 310,728	$ (35,215)	$ 1,070,841	$ (2,666)	$ 7,138