Consolidated Statements Of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
CASH FLOWS FROM OPERATING ACTIVITIES
Net income	$ 207,864	$ 288,399
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	50,617	47,412
Net realized investment losses (gains)	28,458	(197,726)
Increase in premiums receivable	(18,075)	(74,797)
Decrease in reinsurance recoverables	37,241	117,640
Changes in current and deferred income taxes	6,075	60,026
Increase in deferred policy acquisition costs	(18,296)	(22,563)
Increase in loss and loss adjustment expense reserves	20,731	25,799
Increase in unearned premiums	77,002	147,784
Increase in accounts payable and accrued expenses	38,879	40,764
Share-based compensation	106	88
Other, net	12,650	(19,233)
Net cash provided by operating activities	443,252	413,593
Fixed maturity securities available for sale in nature:
Purchases	(686,541)	(384,991)
Sales	127,336	55,882
Calls or maturities	154,180	258,810
Equity securities available for sale in nature:
Purchases	(1,001,624)	(852,903)
Sales	849,964	805,752
Calls	3,880	0
Changes in securities payable and receivable	11,923	3,771
Decrease (increase) in short-term investments	240,673	(168,378)
Purchases of fixed assets	(29,764)	(31,824)
Other, net	19,078	4,972
Net cash used in investing activities	(310,895)	(308,909)
CASH FLOWS FROM FINANCING ACTIVITIES
Dividends paid to shareholders	(104,626)	(104,196)
Proceeds from stock options exercised	0	591
Net cash used in financing activities	(104,626)	(103,605)
Net increase in cash	27,731	1,079
Cash:
Beginning of the year	294,398	314,291
End of period	322,129	315,370
SUPPLEMENTAL CASH FLOW DISCLOSURE
Interest paid	16,573	16,567
Income taxes paid, net	$ 37,453	$ 1,178