Condensed Financial Information of Registrant (Schedule Of Condensed Financial Information Of Registrant, Statements Of Cash Flow) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Cash flows from operating activities:
Net cash provided by operating activities	$ 352,589,000	$ 501,584,000	$ 605,616,000
Cash flows from investing activities:
Capital distribution from subsidiaries	2,900,000	5,200,000	12,100,000
Fixed maturity securities available for sale in nature:
Purchases	(1,794,817,000)	(1,460,641,000)	(878,213,000)
Sales	856,291,000	336,201,000	168,087,000
Equity securities available for sale in nature
Purchases	(1,042,913,000)	(958,008,000)	(1,230,785,000)
Sales	1,154,523,000	943,857,000	1,174,540,000
Other, net	5,752,000	9,096,000	20,577,000
Net cash used in investing activities	(316,384,000)	(373,670,000)	(411,286,000)
Cash flows from financing activities:
Dividends paid to shareholders	(105,482,000)	(140,226,000)	(139,640,000)
Proceeds from stock options exercised	0	215,000	0
Proceeds from bank loan	25,000,000	0	0
Net cash used in financing activities	(81,986,000)	(140,836,000)	(140,249,000)
Net (decrease) increase in cash	(45,781,000)	(12,922,000)	54,081,000
Cash:
Beginning of year	335,557,000	348,479,000	294,398,000
End of year	289,776,000	335,557,000	348,479,000
SUPPLEMENTAL CASH FLOW DISCLOSURE
Interest paid	16,665,000	16,616,000	16,599,000
Income taxes (refunded) paid, net	(26,542,000)	69,467,000	52,659,000
Parent Company
Cash flows from operating activities:
Net cash provided by operating activities	225,000	(36,662,000)	(17,339,000)
Cash flows from investing activities:
Capital contribution to subsidiaries	0	0	(30,000,000)
Capital distribution from subsidiaries	3,431,433	0	0
Distributions received from special purpose entities	2,904,000	5,199,000	12,129,000
Dividends received from subsidiaries	0	191,000,000	121,000,000
Fixed maturity securities available for sale in nature:
Purchases	(11,905,000)	0	0
Sales	1,000,000	0	0
Equity securities available for sale in nature
Purchases	(5,307,000)	(13,151,000)	(54,571,000)
Sales	48,215,000	38,092,000	67,965,000
(Increase) decrease in short-term investments	(6,268,000)	(16,172,000)	25,088,000
Other, net	667,000	791,000	254,000
Net cash used in investing activities	32,737,000	205,759,000	141,865,000
Cash flows from financing activities:
Dividends paid to shareholders	(105,482,000)	(140,226,000)	(139,640,000)
Proceeds from stock options exercised	0	215,000	0
Proceeds from bank loan	25,000,000	0	0
Net cash used in financing activities	(80,482,000)	(140,011,000)	(139,640,000)
Net (decrease) increase in cash	(47,520,000)	29,086,000	(15,114,000)
Cash:
Beginning of year	53,738,000	24,652,000	39,766,000
End of year	6,218,000	53,738,000	24,652,000
SUPPLEMENTAL CASH FLOW DISCLOSURE
Interest paid	16,611,000	16,590,000	16,586,000
Income taxes (refunded) paid, net	$ (14,102,000)	$ 18,841,000	$ (20,552,000)