Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Operating activities
Net earnings	$ 107,911	$ 105,850
Adjustments to reconcile net earnings to net cash provided by operating activities:
Change in premium, claims and other receivables	(44,966)	(29,047)
Change in reinsurance recoverables	55,197	1,364
Change in ceded unearned premium	(5,939)	(528)
Change in loss and loss adjustment expense payable	(53,892)	16,429
Change in unearned premium	32,475	16,236
Change in reinsurance, premium and claims payable	71,873	26,113
Change in accounts payable and accrued liabilities	(51,885)	(101,424)
Stock-based compensation expense	4,214	2,874
Depreciation and amortization expense	4,169	4,797
Gain on investments	(20,246)	(8,570)
Other, net	(3,447)	(31,997)
Cash provided by operating activities	95,464	2,097
Investing activities
Sales of available for sale fixed maturity securities	119,011	158,135
Sales of equity securities	144,075	17,808
Sales of other investments	0	20,921
Maturity or call of available for sale fixed maturity securities	131,204	190,308
Cost of available for sale fixed maturity securities acquired	(179,789)	(389,731)
Cost of equity securities acquired	(70,841)	(69,255)
Change in short-term investments	(248,749)	95,352
Payments for purchase of businesses, net of cash received	(2,579)	(8,214)
Other, net	(2,224)	(344)
Cash provided (used) by investing activities	(109,892)	14,980
Financing activities
Advances on line of credit	100,000	50,000
Payments on line of credit	(30,000)	(15,000)
Sale of common stock	8,428	6,919
Purchase of common stock	(30,774)	(34,426)
Dividends paid	(22,575)	(16,674)
Other, net	3,572	(3,609)
Cash provided (used) by financing activities	28,651	(12,790)
Net increase in cash	14,223	4,287
Cash at beginning of year	58,301	71,390
Cash at end of period	$ 72,524	$ 75,677