Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Mar. 31, 2012		Dec. 31, 2011
Available-for-sale securities at fair value:
Equity securities (cost: 2012 - $659,202; 2011 - $775,741)	$ 773,886		$ 870,950
Debt securities (amortized cost: 2012 - $15,624,969; 2011 - $2,538,872)	15,733,901		2,679,528
Short-term investments	571,748		1,096,517
Marketable Securities, Total	17,079,535		4,646,995
Other invested assets	434,921		179,815
Total investments	17,514,456		4,826,810
Cash	520,216		84,749
Accrued investment income	167,460		28,879
Premium balances receivable	855,945		147,006
Reinsurance recoverables	1,324,420	[1]	852,845
Ceded unearned premiums	146,449		142,946
Deferred acquisition costs	117,077		70,537
Property and equipment at cost, net of accumulated depreciation and amortization	22,304		17,906
Goodwill	48,095		48,095
Intangible assets, net of amortization	382,473		90,863
Current taxes receivable	40,531
Net deferred tax assets	486,247		80,975
Other assets	149,481		86,478
Total assets	21,775,154		6,478,089
Liabilities and Stockholders' Equity
Loss and loss adjustment expenses	11,870,264		2,313,035
Unearned premiums	1,708,610		549,740
Senior Notes	1,423,883		299,035
Reinsurance payable	73,452		45,462
Current taxes payable			16,247
Other liabilities	515,845		328,893
Total liabilities	15,592,054		3,552,412
Common stock (shares authorized: 2012 and 2011 - 22,000,000; issued 2012 - 17,478,746; 2011 - 9,117,787)	17,479		9,118
Contributed capital	3,626,154		938,037
Accumulated other comprehensive income	152,360		155,532
Treasury stock, at cost (2012 - 550,082 shares; 2011 - 566,141 shares)	(162,573)		(167,319)
Retained earnings	2,549,680		1,990,309
Total stockholders' equity	6,183,100		2,925,677
Liabilities and Equity, Total	$ 21,775,154		$ 6,478,089

[1] Reinsurance recoverables reflect amounts due from one or more reinsurance subsidiaries of the listed company.