Consolidated Statements Of Income And Comprehensive Income (Loss) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
OPERATING REVENUES
Earned premiums	$ 950,859	$ 957,557	$ 1,908,545	$ 1,901,207
Net investment income	94,996	90,586	186,290	183,461
Other-than-temporary impairment losses	(3,675)	0	(12,080)	(5,092)
Net realized investment gains, excluding other-than-temporary impairment losses	20,916	6,105	50,500	16,768
Net realized investment gains	17,241	6,105	38,420	11,676
Other revenues	312,841	250,357	618,864	510,415
Total Operating Revenues	1,375,937	1,304,605	2,752,119	2,606,759
OPERATING EXPENSES
Losses and loss adjustment expenses	511,556	536,194	985,520	983,189
Underwriting, acquisition and insurance expenses	375,580	379,652	740,268	720,337
Amortization of intangible assets	17,204	16,949	34,464	31,589
Other expenses	277,909	242,236	553,002	473,237
Total Operating Expenses	1,182,249	1,175,031	2,313,254	2,208,352
Operating Income	193,688	129,574	438,865	398,407
Interest expense	33,697	29,288	64,538	58,600
Loss on early extinguishment of debt	44,100	0	44,100	0
Income Before Income Taxes	115,891	100,286	330,227	339,807
Income tax expense	35,218	7,833	85,908	53,348
Net Income	80,673	92,453	244,319	286,459
Net income attributable to noncontrolling interests	1,876	1,084	5,152	4,098
Net Income to Shareholders	78,797	91,369	239,167	282,361
OTHER COMPREHENSIVE INCOME (LOSS)
Net holding gains (losses) arising during the period	149,406	(230,142)	388,296	(109,120)
Change in unrealized other-than-temporary impairment losses on fixed maturities arising during the period	44	(48)	(23)	119
Reclassification adjustments for net gains included in net income	(10,567)	(4,984)	(23,550)	(14,037)
Change in net unrealized gains on investments, net of taxes	138,883	(235,174)	364,723	(123,038)
Change in foreign currency translation adjustments, net of taxes	(8,121)	10,385	2,208	(11,429)
Change in net actuarial pension loss, net of taxes	394	469	857	932
Total Other Comprehensive Income (Loss)	131,156	(224,320)	367,788	(133,535)
Comprehensive Income (Loss)	211,829	(131,867)	612,107	152,924
Comprehensive income attributable to noncontrolling interests	1,887	1,058	5,171	4,042
Comprehensive Income (Loss) to Shareholders	$ 209,942	$ (132,925)	$ 606,936	$ 148,882
NET INCOME PER SHARE
Basic (in dollars per share)	$ 5.44	$ 6.76	$ 16.65	$ 20.33
Diluted (in dollars per share)	$ 5.41	$ 6.72	$ 16.55	$ 20.21