CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $) In Millions, except Per Share data, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011
Fixed maturities, amortized cost	$ 8,212	$ 8,084
Equity securities, cost	2,158	2,162
Land, building and equipment, accumulated depreciation	$ 383	$ 376
Common stock, par value	$ 2	$ 2
Common stock, authorized	500	500
Common stock, issued	196	196
Treasury stock, shares	34	34