Investments (Net Investment Income) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Net Investment Income [Line Items]
Less: Investment expenses	$ 302	$ 276	$ 889	$ 793
Subtotal	5,026	5,517	16,385	16,436
Securities Investment [Member]
Net Investment Income [Line Items]
Subtotal	5,163	5,235	15,683	15,907
Subtotal	4,861	4,959	14,794	15,114
Debt Securities [Member]
Net Investment Income [Line Items]
Subtotal	3,784	3,825	11,319	11,370
Equity Securities [Member]
Net Investment Income [Line Items]
Subtotal	28	26	88	96
Actively traded securities and FVO general account securities [Member]
Net Investment Income [Line Items]
Subtotal	14	24	24	68
Changes in estimated fair value included in net investment income	2	6	(14)	36
Mortgage Loans on Real Estate [Member]
Net Investment Income [Line Items]
Subtotal	725	811	2,179	2,405
Policy Loans [Member]
Net Investment Income [Line Items]
Subtotal	158	157	465	471
Real Estate Investment [Member]
Net Investment Income [Line Items]
Subtotal	227	173	663	630
Partnership Interest [Member]
Net Investment Income [Line Items]
Subtotal	144	145	665	593
Cash and Cash Equivalents [Member]
Net Investment Income [Line Items]
Subtotal	42	40	136	115
International Joint Venture [Member]
Net Investment Income [Line Items]
Subtotal	16	7	7	11
Other Investments [Member]
Net Investment Income [Line Items]
Subtotal	25	27	137	148
Consolidated Securitization Entities And Fair Value Option Contractholder-Directed Unit-Linked [Member]
Net Investment Income [Line Items]
Subtotal	165	558	1,591	1,322
FVO contractholder-directed unit-linked investments [Member]
Net Investment Income [Line Items]
Subtotal	132	512	1,485	1,010
Changes in estimated fair value included in net investment income	(9)	247	1,069	741
Securitized Reverse Residential Mortgage Loan [Member]
Net Investment Income [Line Items]
Subtotal	0	3	0	177
Commercial Loan [Member] | Consolidated Securitization Entities [Member]
Net Investment Income [Line Items]
Subtotal	33	42	104	131
Available-for-sale Securities [Member] | Consolidated Securitization Entities [Member]
Net Investment Income [Line Items]
Subtotal	$ 0	$ 1	$ 2	$ 4