Consolidated Statements Of Cash Flows - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
CASH FLOWS FROM OPERATING ACTIVITIES
Net (loss) income	$ (512,672)	$ 247,937	$ 374,607
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	82,390	79,056	68,463
Net realized investment losses (gains)	488,080	(111,658)	(85,731)
Decrease (increase) in premiums receivable	49,630	(26,670)	13,946
Decrease in reinsurance recoverables	19,105	3,488	30,127
Changes in current and deferred income taxes	(131,500)	(18,097)	31,236
Increase in deferred policy acquisition costs	(8,216)	(11,265)	(13,828)
Increase in loss and loss adjustment expense reserves	358,480	235,126	70,049
Increase in unearned premiums	25,840	113,926	50,326
(Decrease) increase in accounts payable and accrued expenses	(15,844)	(26,724)	51,988
Other, net	(2,704)	16,465	14,433
Net cash provided by operating activities	352,589	501,584	605,616
Fixed maturity securities available for sale in nature:
Purchases	(1,794,817)	(1,460,641)	(878,213)
Sales	856,291	336,201	168,087
Calls or maturities	480,023	518,557	250,878
Equity securities available for sale in nature
Purchases	(1,042,913)	(958,008)	(1,230,785)
Sales	1,154,523	943,857	1,174,540
Calls	0	0	3,880
Changes in securities payable and receivable	22,124	8,327	873
Decrease in short-term investments	38,141	270,383	118,830
Purchases of fixed assets	(35,508)	(41,442)	(39,953)
Other, net	5,752	9,096	20,577
Net cash used in investing activities	(316,384)	(373,670)	(411,286)
CASH FLOWS FROM FINANCING ACTIVITIES
Dividends paid to shareholders	(105,482)	(140,226)	(139,640)
Proceeds from stock options exercised	0	215	0
Payments on finance lease obligations	(1,504)	(825)	(609)
Proceeds from bank loan	25,000	0	0
Net cash used in financing activities	(81,986)	(140,836)	(140,249)
Net (decrease) increase in cash	(45,781)	(12,922)	54,081
Cash:
Beginning of year	335,557	348,479	294,398
End of year	289,776	335,557	348,479
SUPPLEMENTAL CASH FLOW DISCLOSURE
Interest paid	16,665	16,616	16,599
Income taxes (refunded) paid, net	$ (26,542)	$ 69,467	$ 52,659

Payments to Acquire Equity Securities Available-for-Sale [Abstract]

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Proceeds From Calls Of Available For Sale Securities

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Amount of cash and cash equivalents, and cash and cash equivalents restricted to withdrawal or usage. Excludes amount for disposal group and discontinued operations. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Amount of cash outflow for principal payment on finance lease.

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