Closed Block (Liabilities and Assets) (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Closed Block Liabilities
Future policy benefits	$ 41,929	$ 42,076
Other policy-related balances	328	298
Policyholder dividends payable	470	456
Policyholder dividend obligation	2,463	1,771	3,828
Current income tax payable	15	18
Other liabilities	608	582
Total closed block liabilities	45,813	45,201
Assets Designated to the Closed Block
Fixed maturity securities available-for-sale, at estimated fair value	28,810	28,374
Equity securities available-for-sale, at estimated fair value	90	86
Mortgage loans	6,117	6,155
Policy loans	4,647	4,669
Real estate and real estate joint ventures	509	492
Other invested assets	935	814
Total investments	41,108	40,590
Cash and cash equivalents	375	238
Accrued investment income	496	477
Premiums, reinsurance and other receivables	67	98
Deferred income tax assets	292	293
Total assets designated to the closed block	42,338	41,696
Excess of closed block liabilities over assets designated to the closed block	3,475	3,505
Amounts included in accumulated other comprehensive income (loss) (“AOCI”):
Unrealized investment gains (losses), net of income tax	1,931	1,502
Unrealized gains (losses) on derivatives, net of income tax	(3)	(3)
Allocated to policyholder dividend obligation, net of income tax	(1,601)	(1,151)
Total amounts included in AOCI	327	348
Maximum future earnings to be recognized from closed block assets and liabilities	$ 3,802	$ 3,853