Closed Block (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011
Closed Block Liabilities
Future policy benefits	$ 43,023	$ 43,169
Other policy-related balances	341	358
Policyholder dividends payable	532	514
Policyholder dividend obligation	2,700	2,919
Other liabilities	689	613
Total closed block liabilities	47,285	47,573
Assets Designated to the Closed Block
Fixed maturity securities available-for-sale, at estimated fair value	30,216	30,407
Equity securities available-for-sale, at estimated fair value	22	35
Mortgage loans	6,228	6,206
Policy loans	4,651	4,657
Real estate and real estate joint ventures	318	364
Other invested assets	854	857
Total investments	42,289	42,526
Cash and cash equivalents	271	249
Accrued investment income	522	509
Premiums, reinsurance and other receivables	78	109
Current income tax recoverable	27	53
Deferred income tax assets	368	362
Total assets designated to the closed block	43,555	43,808
Excess of closed block liabilities over assets designated to the closed block	3,730	3,765
Amounts included in accumulated other comprehensive income (loss):
Unrealized investment gains (losses), net of income tax	2,237	2,394
Unrealized gains (losses) on derivative instruments, net of income tax	9	11
Allocated to policyholder dividend obligation, net of income tax	(1,755)	(1,897)
Total amounts included in accumulated other comprehensive income (loss)	491	508
Maximum future earnings to be recognized from closed block assets and liabilities	$ 4,221	$ 4,273