Condensed Consolidated Balance Sheets (USD $) In Millions, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Investments
Fixed maturities, at fair value (amortized cost: 2012-$8,233; 2011-$8,084)	$ 9,116	$ 8,779
Equity securities, at fair value (cost: 2012-$2,315; 2011-$2,162)	3,349	2,956
Other invested assets	68	66
Total investments	12,533	11,801
Cash and cash equivalents	416	438
Investment income receivable	116	119
Finance receivable	76	76
Premiums receivable	1,247	1,087
Reinsurance recoverable	589	622
Prepaid reinsurance premiums	26	24
Deferred policy acquisition costs	491	477
Land, building and equipment, net, for company use (accumulated depreciation: 2012-$390; 2011-$376)	223	227
Other assets	47	93
Separate accounts	715	671
Total assets	16,479	15,635
Insurance reserves
Loss and loss expense reserves	4,344	4,339
Life policy and investment contract reserves	2,285	2,214
Unearned premiums	1,818	1,633
Other liabilities	573	517
Deferred income tax	453	303
Note payable	104	104
Long-term debt and capital lease obligations	828	821
Separate accounts	715	671
Total liabilities	11,120	10,602
Commitments and contingent liabilities (Note 13)
SHAREHOLDERS' EQUITY
Common stock, par value-$2 per share; (authorized: 2012 and 2011-500 million shares; issued and outstanding: 2012-197 million shares and 2011-196 million shares)	394	393
Paid-in capital	1,119	1,096
Retained earnings	3,896	3,863
Accumulated other comprehensive income	1,171	901
Treasury stock at cost (2012 and 2011-34 million shares)	(1,221)	(1,220)
Total shareholders' equity	5,359	5,033
Total liabilities and shareholders' equity	$ 16,479	$ 15,635