Schedule II - Condensed Financial Information of the Registrant Cash Flow (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Condensed Statements of Cash Flows
Net income	$ 130,710	$ 138,211	$ 99,601
Adjustments to reconcile net income to net cash provided by operating activities:
Earnings from consolidated subsidiaries	(4,895)	(1,378)	(1,552)
Changes in assets and liabilities:
Other assets	(3,346)	(15)	(1,864)
Accounts payable and accrued liabilities	(2,876)	4,310	3,395
Net cash provided by operating activities	141,394	109,460	112,456
Long-term Line of Credit	30,000	30,000
Dividends paid	(54,008)	(54,575)	(52,667)
Net cash used for financing activities	(65,571)	(64,574)	(52,667)
Net increase in cash and cash equivalents	9,834	9,362	6,825
Cash and cash equivalents at beginning of year	53,769	44,407	37,582
Cash and cash equivalents at end of period	63,603	53,769	44,407
Registrant
Condensed Statements of Cash Flows
Net income	130,710	138,211	99,601
Adjustments to reconcile net income to net cash provided by operating activities:
Earnings from consolidated subsidiaries	(132,465)	(140,044)	(101,295)
Dividends received from consolidated subsidiaries	49,488	89,156	47,585
Amortization of restricted stock expense	17,788	7,359	6,514
Changes in assets and liabilities:
Other assets	15	15	15
Accounts payable and accrued liabilities	35	(123)	247
Net cash provided by operating activities	65,571	94,574	52,667
Dividends paid	(54,008)	(54,575)	(52,667)
Acquisition of treasury stock	(11,563)	(39,999)
Net cash used for financing activities	$ (65,571)	$ (94,574)	$ (52,667)