Fair Value (Recurring Fair Value Measurements) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Assets [Abstract]
Available-for-sale Securities, Debt Securities	$ 188,911	$ 173,746
Available-for-sale Securities, Equity Securities	2,065	1,892
Actively Traded Securities	654	662
Fair Value Option And Trading Securities	705	723
Short-term Investments	4,474	5,962
Mortgage loans, under fair value option	49,059	46,024
Derivative assets	7,104	4,141
Net embedded derivatives within asset host contracts	507	(168)
Separate account assets	139,335	134,796
Liabilities [Abstract]
Derivative liabilities	2,732	2,322
Long-term debt, at estimated fair value, relating to variable interest entities	2,027	2,828
Residential mortgage loans — FVO
Assets [Abstract]
Mortgage loans, under fair value option	308	338
Long-term debt
Liabilities [Abstract]
Long-term debt, at estimated fair value, relating to variable interest entities	117	122
Consolidated Securitization Entities
Liabilities [Abstract]
Long-term debt, at estimated fair value, relating to variable interest entities	13	28
Recurring
Assets [Abstract]
Available-for-sale Securities, Debt Securities	188,911	173,746
Available-for-sale Securities, Equity Securities	2,065	1,892
Actively Traded Securities	654	662
Fair Value Option And Trading Securities	705	723
Short-term Investments	4,181	5,786
Derivative assets	7,104	4,141
Net embedded derivatives within asset host contracts	657	(62)
Separate account assets	139,335	134,796
Total assets	343,266	321,360
Liabilities [Abstract]
Derivative liabilities	2,732	2,322
Net embedded derivatives within liability host contracts	731	(106)
Trading liabilities	239	262
Total liabilities	3,832	2,628
Recurring | Interest rate contracts
Assets [Abstract]
Derivative assets	5,541	3,261
Liabilities [Abstract]
Derivative liabilities	1,214	1,154
Recurring | Foreign currency exchange rate contracts
Assets [Abstract]
Derivative assets	1,017	749
Liabilities [Abstract]
Derivative liabilities	971	1,146
Recurring | Credit contracts
Assets [Abstract]
Derivative assets	138	131
Liabilities [Abstract]
Derivative liabilities	16	22
Recurring | Equity market contracts
Assets [Abstract]
Derivative assets	408	0
Liabilities [Abstract]
Derivative liabilities	531	0
Recurring | FVO general account securities
Assets [Abstract]
Fair Value Option And Trading Securities	36	38
Recurring | Residential mortgage loans — FVO
Assets [Abstract]
Mortgage loans, under fair value option	308	338
Recurring | Long-term debt
Liabilities [Abstract]
Long-term debt, at estimated fair value, relating to variable interest entities	117	122
Recurring | Consolidated Securitization Entities
Assets [Abstract]
Fair Value Option And Trading Securities	15	23
Liabilities [Abstract]
Long-term debt, at estimated fair value, relating to variable interest entities	13	28
Recurring | U.S. corporate
Assets [Abstract]
Available-for-sale Securities, Debt Securities	65,357	64,229
Recurring | U.S. Treasury and agency
Assets [Abstract]
Available-for-sale Securities, Debt Securities	39,070	30,544
Recurring | Foreign corporate securities
Assets [Abstract]
Available-for-sale Securities, Debt Securities	29,818	28,756
Recurring | RMBS
Assets [Abstract]
Available-for-sale Securities, Debt Securities	28,163	24,710
Recurring | CMBS
Assets [Abstract]
Available-for-sale Securities, Debt Securities	7,913	8,376
Recurring | ABS
Assets [Abstract]
Available-for-sale Securities, Debt Securities	8,226	7,824
Recurring | State and political subdivision
Assets [Abstract]
Available-for-sale Securities, Debt Securities	6,520	5,777
Recurring | Foreign government
Assets [Abstract]
Available-for-sale Securities, Debt Securities	3,844	3,530
Recurring | Common stock
Assets [Abstract]
Available-for-sale Securities, Equity Securities	1,352	1,164
Recurring | Non-redeemable preferred stock
Assets [Abstract]
Available-for-sale Securities, Equity Securities	713	728
Recurring | Level 1
Assets [Abstract]
Available-for-sale Securities, Debt Securities	21,625	15,858
Available-for-sale Securities, Equity Securities	584	361
Actively Traded Securities	22	2
Fair Value Option And Trading Securities	22	2
Short-term Investments	860	1,387
Derivative assets	10	0
Net embedded derivatives within asset host contracts	0	0
Separate account assets	26,119	28,422
Total assets	49,220	46,030
Liabilities [Abstract]
Derivative liabilities	0	0
Net embedded derivatives within liability host contracts	0	0
Trading liabilities	215	260
Total liabilities	215	260
Recurring | Level 1 | Interest rate contracts
Assets [Abstract]
Derivative assets	0	0
Liabilities [Abstract]
Derivative liabilities	0	0
Recurring | Level 1 | Foreign currency exchange rate contracts
Assets [Abstract]
Derivative assets	0	0
Liabilities [Abstract]
Derivative liabilities	0	0
Recurring | Level 1 | Credit contracts
Assets [Abstract]
Derivative assets	0	0
Liabilities [Abstract]
Derivative liabilities	0	0
Recurring | Level 1 | Equity market contracts
Assets [Abstract]
Derivative assets	10	0
Liabilities [Abstract]
Derivative liabilities	0	0
Recurring | Level 1 | FVO general account securities
Assets [Abstract]
Fair Value Option And Trading Securities	0	0
Recurring | Level 1 | Residential mortgage loans — FVO
Assets [Abstract]
Mortgage loans, under fair value option	0	0
Recurring | Level 1 | Long-term debt
Liabilities [Abstract]
Long-term debt, at estimated fair value, relating to variable interest entities	0	0
Recurring | Level 1 | Consolidated Securitization Entities
Assets [Abstract]
Fair Value Option And Trading Securities	0	0
Liabilities [Abstract]
Long-term debt, at estimated fair value, relating to variable interest entities	0	0
Recurring | Level 1 | U.S. corporate
Assets [Abstract]
Available-for-sale Securities, Debt Securities	0	0
Recurring | Level 1 | U.S. Treasury and agency
Assets [Abstract]
Available-for-sale Securities, Debt Securities	21,625	15,858
Recurring | Level 1 | Foreign corporate securities
Assets [Abstract]
Available-for-sale Securities, Debt Securities	0	0
Recurring | Level 1 | RMBS
Assets [Abstract]
Available-for-sale Securities, Debt Securities	0	0
Recurring | Level 1 | CMBS
Assets [Abstract]
Available-for-sale Securities, Debt Securities	0	0
Recurring | Level 1 | ABS
Assets [Abstract]
Available-for-sale Securities, Debt Securities	0	0
Recurring | Level 1 | State and political subdivision
Assets [Abstract]
Available-for-sale Securities, Debt Securities	0	0
Recurring | Level 1 | Foreign government
Assets [Abstract]
Available-for-sale Securities, Debt Securities	0	0
Recurring | Level 1 | Common stock
Assets [Abstract]
Available-for-sale Securities, Equity Securities	584	361
Recurring | Level 1 | Non-redeemable preferred stock
Assets [Abstract]
Available-for-sale Securities, Equity Securities	0	0
Recurring | Level 2
Assets [Abstract]
Available-for-sale Securities, Debt Securities	152,986	143,616
Available-for-sale Securities, Equity Securities	1,266	1,203
Actively Traded Securities	627	648
Fair Value Option And Trading Securities	652	695
Short-term Investments	3,091	4,224
Derivative assets	6,938	4,101
Net embedded derivatives within asset host contracts	0	0
Separate account assets	111,601	105,165
Total assets	276,534	259,004
Liabilities [Abstract]
Derivative liabilities	2,582	2,318
Net embedded derivatives within liability host contracts	7	4
Trading liabilities	24	2
Total liabilities	2,695	2,403
Recurring | Level 2 | Interest rate contracts
Assets [Abstract]
Derivative assets	5,524	3,258
Liabilities [Abstract]
Derivative liabilities	1,214	1,150
Recurring | Level 2 | Foreign currency exchange rate contracts
Assets [Abstract]
Derivative assets	1,010	735
Liabilities [Abstract]
Derivative liabilities	971	1,146
Recurring | Level 2 | Credit contracts
Assets [Abstract]
Derivative assets	125	108
Liabilities [Abstract]
Derivative liabilities	15	22
Recurring | Level 2 | Equity market contracts
Assets [Abstract]
Derivative assets	279	0
Liabilities [Abstract]
Derivative liabilities	382	0
Recurring | Level 2 | FVO general account securities
Assets [Abstract]
Fair Value Option And Trading Securities	22	24
Recurring | Level 2 | Residential mortgage loans — FVO
Assets [Abstract]
Mortgage loans, under fair value option	0	0
Recurring | Level 2 | Long-term debt
Liabilities [Abstract]
Long-term debt, at estimated fair value, relating to variable interest entities	82	79
Recurring | Level 2 | Consolidated Securitization Entities
Assets [Abstract]
Fair Value Option And Trading Securities	3	23
Liabilities [Abstract]
Long-term debt, at estimated fair value, relating to variable interest entities	0	0
Recurring | Level 2 | U.S. corporate
Assets [Abstract]
Available-for-sale Securities, Debt Securities	60,420	58,960
Recurring | Level 2 | U.S. Treasury and agency
Assets [Abstract]
Available-for-sale Securities, Debt Securities	17,445	14,624
Recurring | Level 2 | Foreign corporate securities
Assets [Abstract]
Available-for-sale Securities, Debt Securities	26,227	25,558
Recurring | Level 2 | RMBS
Assets [Abstract]
Available-for-sale Securities, Debt Securities	24,534	22,197
Recurring | Level 2 | CMBS
Assets [Abstract]
Available-for-sale Securities, Debt Securities	7,464	7,946
Recurring | Level 2 | ABS
Assets [Abstract]
Available-for-sale Securities, Debt Securities	6,734	5,298
Recurring | Level 2 | State and political subdivision
Assets [Abstract]
Available-for-sale Securities, Debt Securities	6,520	5,777
Recurring | Level 2 | Foreign government
Assets [Abstract]
Available-for-sale Securities, Debt Securities	3,642	3,256
Recurring | Level 2 | Common stock
Assets [Abstract]
Available-for-sale Securities, Equity Securities	716	753
Recurring | Level 2 | Non-redeemable preferred stock
Assets [Abstract]
Available-for-sale Securities, Equity Securities	550	450
Recurring | Level 3
Assets [Abstract]
Available-for-sale Securities, Debt Securities	14,300	14,272
Available-for-sale Securities, Equity Securities	215	328
Actively Traded Securities	5	12
Fair Value Option And Trading Securities	31	26
Short-term Investments	230	175
Derivative assets	156	40
Net embedded derivatives within asset host contracts	657	(62)
Separate account assets	1,615	1,209
Total assets	17,512	16,326
Liabilities [Abstract]
Derivative liabilities	150	4
Net embedded derivatives within liability host contracts	724	(110)
Trading liabilities	0	0
Total liabilities	922	(35)
Recurring | Level 3 | Interest rate contracts
Assets [Abstract]
Derivative assets	17	3
Liabilities [Abstract]
Derivative liabilities	0	4
Recurring | Level 3 | Foreign currency exchange rate contracts
Assets [Abstract]
Derivative assets	7	14
Liabilities [Abstract]
Derivative liabilities	0	0
Recurring | Level 3 | Credit contracts
Assets [Abstract]
Derivative assets	13	23
Liabilities [Abstract]
Derivative liabilities	1	0
Recurring | Level 3 | Equity market contracts
Assets [Abstract]
Derivative assets	119	0
Liabilities [Abstract]
Derivative liabilities	149	0
Recurring | Level 3 | FVO general account securities
Assets [Abstract]
Fair Value Option And Trading Securities	14	14
Recurring | Level 3 | Residential mortgage loans — FVO
Assets [Abstract]
Mortgage loans, under fair value option	308	338
Recurring | Level 3 | Long-term debt
Liabilities [Abstract]
Long-term debt, at estimated fair value, relating to variable interest entities	35	43
Recurring | Level 3 | Consolidated Securitization Entities
Assets [Abstract]
Fair Value Option And Trading Securities	12	0
Liabilities [Abstract]
Long-term debt, at estimated fair value, relating to variable interest entities	13	28
Recurring | Level 3 | U.S. corporate
Assets [Abstract]
Available-for-sale Securities, Debt Securities	4,937	5,269
Recurring | Level 3 | U.S. Treasury and agency
Assets [Abstract]
Available-for-sale Securities, Debt Securities	0	62
Recurring | Level 3 | Foreign corporate securities
Assets [Abstract]
Available-for-sale Securities, Debt Securities	3,591	3,198
Recurring | Level 3 | RMBS
Assets [Abstract]
Available-for-sale Securities, Debt Securities	3,629	2,513
Recurring | Level 3 | CMBS
Assets [Abstract]
Available-for-sale Securities, Debt Securities	449	430
Recurring | Level 3 | ABS
Assets [Abstract]
Available-for-sale Securities, Debt Securities	1,492	2,526
Recurring | Level 3 | State and political subdivision
Assets [Abstract]
Available-for-sale Securities, Debt Securities	0	0
Recurring | Level 3 | Foreign government
Assets [Abstract]
Available-for-sale Securities, Debt Securities	202	274
Recurring | Level 3 | Common stock
Assets [Abstract]
Available-for-sale Securities, Equity Securities	52	50
Recurring | Level 3 | Non-redeemable preferred stock
Assets [Abstract]
Available-for-sale Securities, Equity Securities	$ 163	$ 278