Consolidated Statement of Income (Unaudited) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Revenues
Premiums	$ 5,523	$ 5,371
Net investment income	740	779
Fee income	82	74
Net realized investment gains	10	20
Other revenues	37	34
Total revenues	6,392	6,278
Claims and expenses
Claims and claim adjustment expenses	3,364	3,382
Amortization of deferred acquisition costs	971	948
General and administrative expenses	884	883
Interest expense	96	96
Total claims and expenses	5,315	5,309
Income before income taxes	1,077	969
Income tax expense	271	130
Net income	806	839
Net income per share
Net income per share, basic	$ 2.04	$ 1.94
Net income per share, diluted	$ 2.02	$ 1.92
Weighted average number of common shares outstanding
Weighted average number of common shares outstanding, basic	392.0	428.2
Weighted average number of common shares outstanding, diluted	395.8	434.4
Other-than-temporary impairment losses:
Other-than-temporary impairment losses, total gains		2
Other-than-temporary impairment losses, non-credit component of impairments recognized in accumulated other comprehensive income	(4)	(6)
Other-than-temporary impairment losses	(4)	(4)
Other net realized investment gains	14	24
Net realized investment gains	$ 10	$ 20