Consolidated Statements Of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
CASH FLOWS FROM OPERATING ACTIVITIES
Net income	$ 74,479	$ 177,949	$ 112,143
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	26,478	28,054	30,587
Net realized investment losses (gains)	83,807	(81,184)	11,422
Bond amortization, net	21,360	18,918	12,529
Excess tax benefit from exercise of stock options	(27)	(148)	(202)
Increase in premiums receivable	(41,512)	(23,934)	(20,688)
Changes in current and deferred income taxes	(35,287)	8,343	3,451
Increase in deferred policy acquisition costs	(4,560)	(2,736)	(8,556)
Increase in unpaid losses and loss adjustment expenses	(36,214)	(52,813)	(2,861)
Increase in unearned premiums	42,552	46,271	33,098
(Decrease) increase in accounts payable and accrued expenses	(35,086)	31,019	30,367
Share-based compensation	(5,208)	(4,112)	(974)
Increase (decrease) in other payables	18,114	(10,988)	12,135
Other, net	(1,496)	(1,954)	(10,317)
Net cash provided by operating activities	190,244	246,535	209,804
CASH FLOWS FROM INVESTING ACTIVITIES
Fixed maturity securities available-for-sale in nature: Purchases	(965,701)	(542,494)	(831,796)
Fixed maturity securities available-for-sale in nature: Sales	260,946	209,680	228,116
Fixed maturity securities available-for-sale in nature: Calls or maturities	386,644	330,637	343,628
Equity securities available for sale in nature:
Purchases	(748,217)	(868,383)	(596,883)
Sales	805,417	745,058	872,997
Calls	2,851	1,044	0
Changes in securities payable and receivable	(1,387)	9,294	1,702
Net decrease (increase) in short-term investments and purchased options	187,492	(56,530)	(20,005)
Purchase of fixed assets	(20,112)	(26,037)	(18,671)
Sale of fixed assets	141	224	820
Business acquisition, net of cash acquired	7,771	0	0
Other, net	2,473	3,472	1,741
Net cash used in investing activities	(81,682)	(194,035)	(18,351)
CASH FLOWS FROM FINANCING ACTIVITIES
Dividends paid to shareholders	(136,386)	(135,496)	(134,776)
Excess tax benefit from exercise of stock options	27	148	202
Proceeds from stock options exercised	2,111	6,247	1,446
Proceeds from bank loan	0	100,000	50,000
Net cash used in financing activities	(134,248)	(29,101)	(83,128)
Net (decrease) increase in cash	(25,686)	23,399	108,325
Cash:
Beginning of year	289,907	266,508	158,183
End of year	264,221	289,907	266,508
SUPPLEMENTAL CASH FLOW DISCLOSURE
Interest paid	2,989	2,543	998
Income taxes paid	$ 31,390	$ 61,139	$ 16,503