Consolidated Statements of Earnings and Comprehensive Income (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Revenues
Net premiums earned	$ 1,075,013	$ 434,207
Net investment income	118,811	53,194
Net realized capital gains	50,902	67,989
Other than temporary impairment losses	(32,312)	(1,778)
Gain on bargain purchase		494,940
Other income	11,141	315
Total revenues	1,223,555	1,048,867
Costs and Expenses
Net loss and loss adjustment expenses	567,413	233,946
Commissions, brokerage and other underwriting expenses	326,227	99,860
Other operating expenses	30,738	15,652
Corporate administration	12,422	47,293
Amortization of intangible assets	11,630	31,939
Interest expense	21,736	9,077
Total costs and expenses	970,166	437,767
Earnings before income taxes	253,389	611,100
Income taxes	57,095	50,997
Net earnings	196,294	560,103
Other comprehensive income:
Change in unrealized gains (losses), net of deferred taxes of $45,877 and $20,145 for 2013 and 2012, respectively	85,200	37,412
Less: reclassification for net realized capital gains and other than temporary impairment losses, net of taxes of $(6,507) and $(23,174) for 2013 and 2012, respectively	(12,084)	(43,037)
Change in unrealized currency translation adjustment, net of deferred taxes of $(5,366) and $1,730 for 2013 and 2012, respectively	(9,966)	3,213
Retirement plans	(154)	(760)
Comprehensive income	$ 259,290	$ 556,931
Basic earnings per share	$ 11.67	$ 51.17
Diluted earnings per share	$ 11.67	$ 51.06