Derivative Financial Instruments (Details) (USD $) In Millions, except Share data, unless otherwise specified	6 Months Ended
	Jun. 30, 2014 contract	Dec. 31, 2013 contract
Derivative Financial Instruments
Assumed recoveries under sale of credit protection	$ 0
Securities pledged in the form of margin deposits	26
Derivatives, Fair Value
Total asset derivatives, Notional amount	213	1,649
Total liability derivatives, Notional amount	3,612	10,760
Total derivatives, Notional amount	3,825	12,409
Total asset derivatives, Number of contracts	4,089	10,662
Total liability derivatives, Number of contracts	3,571	10,035
Total derivatives, Number of contracts	7,660	20,697
Total asset derivatives, Fair value, net	92	254
Asset derivatives, Gross asset	92	266
Asset derivatives, Gross liability	0	(12)
Derivative liabilities net amount on balance sheet	(389)	(741)
Total derivatives, Fair value, net	(297)	(487)
Liability derivatives, Gross asset	7	11
Liability derivatives, Gross liability	(396)	(752)
Number of stock warrants held by the company related to derivative contracts (in shares)		837,100
Derivatives not designated as accounting hedging instruments
Derivatives, Fair Value
Total asset derivatives, Notional amount	197	1,633
Total liability derivatives, Notional amount	3,493	10,628
Total asset derivatives, Number of contracts	4,089	10,662
Total liability derivatives, Number of contracts	3,571	10,035
Total asset derivatives, Fair value, net	92	253
Asset derivatives, Gross asset	92	265
Asset derivatives, Gross liability		(12)
Derivative liabilities net amount on balance sheet	(374)	(726)
Liability derivatives, Gross asset	7	11
Liability derivatives, Gross liability	(381)	(737)
Interest rate swap agreements | Derivatives not designated as accounting hedging instruments | Other liabilities and accrued expenses
Derivatives, Fair Value
Total liability derivatives, Notional amount	85	85
Derivative liabilities net amount on balance sheet	5	4
Liability derivatives, Gross asset	5	4
Other contracts | Derivatives not designated as accounting hedging instruments | Other assets
Derivatives, Fair Value
Total asset derivatives, Notional amount	4	4
Total asset derivatives, Fair value, net	1
Asset derivatives, Gross asset	1
Foreign currency swap agreements | Derivatives designated as accounting hedging instruments | Other investments
Derivatives, Fair Value
Total asset derivatives, Notional amount	16	16
Total asset derivatives, Fair value, net		1
Asset derivatives, Gross asset		1
Foreign currency swap agreements | Derivatives designated as accounting hedging instruments | Other liabilities and accrued expenses
Derivatives, Fair Value
Total liability derivatives, Notional amount	119	132
Derivative liabilities net amount on balance sheet	(15)	(15)
Liability derivatives, Gross liability	(15)	(15)
Interest rate swaption agreements | Derivatives not designated as accounting hedging instruments | Other investments
Derivatives, Fair Value
Total asset derivatives, Notional amount		1,420
Interest rate swaption agreements | Derivatives not designated as accounting hedging instruments | Other liabilities and accrued expenses
Derivatives, Fair Value
Total liability derivatives, Notional amount		4,570
Derivative liabilities net amount on balance sheet		1
Liability derivatives, Gross asset		1
Interest rate cap agreements | Derivatives not designated as accounting hedging instruments | Other investments
Derivatives, Fair Value
Total asset derivatives, Notional amount	79	61
Total asset derivatives, Fair value, net	1	2
Asset derivatives, Gross asset	1	2
Interest rate cap agreements | Derivatives not designated as accounting hedging instruments | Other liabilities and accrued expenses
Derivatives, Fair Value
Total liability derivatives, Notional amount	136	262
Derivative liabilities net amount on balance sheet	2	4
Liability derivatives, Gross asset	2	4
Financial futures contracts - Equity and index contracts | Derivatives not designated as accounting hedging instruments | Other assets
Derivatives, Fair Value
Total asset derivatives, Number of contracts	368	627
Options and warrants | Derivatives not designated as accounting hedging instruments | Other investments
Derivatives, Fair Value
Total asset derivatives, Notional amount		3
Total asset derivatives, Number of contracts		10,035
Total asset derivatives, Fair value, net		261
Asset derivatives, Gross asset		261
Options | Derivatives not designated as accounting hedging instruments | Other investments
Derivatives, Fair Value
Total asset derivatives, Number of contracts	3,721
Total asset derivatives, Fair value, net	88
Asset derivatives, Gross asset	88
Options and futures | Derivatives not designated as accounting hedging instruments | Other liabilities and accrued expenses
Derivatives, Fair Value
Total liability derivatives, Notional amount		55
Total liability derivatives, Number of contracts	3,571	10,035
Derivative liabilities net amount on balance sheet	(40)	(165)
Liability derivatives, Gross asset		2
Liability derivatives, Gross liability	(40)	(167)
Foreign currency forwards | Derivatives not designated as accounting hedging instruments | Other investments
Derivatives, Fair Value
Total asset derivatives, Notional amount	9	47
Foreign currency forwards | Derivatives not designated as accounting hedging instruments | Other liabilities and accrued expenses
Derivatives, Fair Value
Total liability derivatives, Notional amount	46
Credit default swaps | Derivatives not designated as accounting hedging instruments | Fixed income securities
Derivatives, Fair Value
Total asset derivatives, Notional amount		12
Total asset derivatives, Fair value, net		(12)
Asset derivatives, Gross liability		(12)
Guaranteed accumulation benefits | Derivatives not designated as accounting hedging instruments | Contractholder funds
Derivatives, Fair Value
Total liability derivatives, Notional amount	674	738
Derivative liabilities net amount on balance sheet	(38)	(43)
Liability derivatives, Gross liability	(38)	(43)
Guaranteed withdrawal benefits | Derivatives not designated as accounting hedging instruments | Contractholder funds
Derivatives, Fair Value
Total liability derivatives, Notional amount	473	506
Derivative liabilities net amount on balance sheet	(13)	(13)
Liability derivatives, Gross liability	(13)	(13)
Equity-indexed and forward starting options in life and annuity product contracts | Derivatives not designated as accounting hedging instruments | Contractholder funds
Derivatives, Fair Value
Total liability derivatives, Notional amount	1,770	1,693
Derivative liabilities net amount on balance sheet	(275)	(247)
Liability derivatives, Gross liability	(275)	(247)
Equity-indexed and forward starting options in life and annuity product contracts | Derivatives not designated as accounting hedging instruments | Liabilities held for sale
Derivatives, Fair Value
Total liability derivatives, Notional amount		2,363
Derivative liabilities net amount on balance sheet		(246)
Liability derivatives, Gross liability		(246)
Other embedded derivative financial instruments | Derivatives not designated as accounting hedging instruments | Contractholder funds
Derivatives, Fair Value
Total liability derivatives, Notional amount	85	85
Derivative liabilities net amount on balance sheet	(5)	(4)
Liability derivatives, Gross liability	(5)	(4)
Credit default swaps - buying protection | Derivatives not designated as accounting hedging instruments | Other investments
Derivatives, Fair Value
Total asset derivatives, Notional amount	20	1
Credit default swaps - buying protection | Derivatives not designated as accounting hedging instruments | Other liabilities and accrued expenses
Derivatives, Fair Value
Total liability derivatives, Notional amount	124	171
Derivative liabilities net amount on balance sheet	(2)	(2)
Liability derivatives, Gross liability	(2)	(2)
Credit default swaps - selling protection | Derivatives not designated as accounting hedging instruments | Other investments
Derivatives, Fair Value
Total asset derivatives, Notional amount	85	85
Total asset derivatives, Fair value, net	2	2
Asset derivatives, Gross asset	2	2
Credit default swaps - selling protection | Derivatives not designated as accounting hedging instruments | Other liabilities and accrued expenses
Derivatives, Fair Value
Total liability derivatives, Notional amount	100	100
Derivative liabilities net amount on balance sheet	(8)	(15)
Liability derivatives, Gross liability	$ (8)	$ (15)