Restructuring and Other Costs (Details 3) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	$ 53	$ 14	$ 110	$ 14
Restructuring and Related Cost, Expected Cost			250
Property Casualty Commercial [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	1	0	5	0
Restructuring and Related Cost, Expected Cost			7
Group Benefits [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	1	0	1	0
Restructuring and Related Cost, Expected Cost			1
Consumer Markets [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	0	0	1	0
Restructuring and Related Cost, Expected Cost			3
Individual Life [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	18	0	25	0
Restructuring and Related Cost, Expected Cost			30
Retirement [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	10	0	14	0
Restructuring and Related Cost, Expected Cost			16
Mutual Funds [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	1	0	2	0
Restructuring and Related Cost, Expected Cost			4
Life Other Operations [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	5	0	8	0
Restructuring and Related Cost, Expected Cost			12
Corporate [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	17	14	54	14
Restructuring and Related Cost, Expected Cost			$ 177