Derivative Instruments (Total Fair Value Of Company's Derivative Assets And Liabilities By Instrument And Balance Sheet Location, Before Counterparty Netting) (Detail) (USD $) In Millions, unless otherwise specified	Mar. 31, 2014		Dec. 31, 2013
Derivative [Line Items]
Derivative notional amount	$ 23,389		$ 31,316
Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative notional amount	23,389		31,316
Derivative Liabilities [Member]
Derivative [Line Items]
Derivative liabilities, Total derivatives	(560)	[1]	(1,347)	[1]
Derivative Liabilities [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative Liabilities, Not designated, Fair Value	(560)	[1]	(1,347)	[1]
Derivative Assets [Member]
Derivative [Line Items]
Derivative assets, Total assets	68	[1]	55	[1]
Derivative Assets [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative Assets, Not designated, Fair Value	68	[1]	55	[1]
Interest Rate Swap [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative notional amount	1,487		1,495
Interest Rate Swap [Member] | Derivative Liabilities [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative Liabilities, Not designated, Fair Value	(190)	[1]	(165)	[1]
Interest Rate Swap [Member] | Other Assets [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative Assets, Not designated, Fair Value	58	[1]	46	[1]
Credit Default Swap [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative notional amount	16,682		23,954
Credit Default Swap [Member] | Derivative Liabilities [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative Liabilities, Not designated, Fair Value	(309)	[1]	(1,132)	[1]
Credit Default Swap [Member] | Other Assets [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative Assets, Not designated, Fair Value	0	[1]	0	[1]
Insured Swaps [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative notional amount	4,270		4,945
Insured Swaps [Member] | Derivative Liabilities [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative Liabilities, Not designated, Fair Value	(4)	[1]	(5)	[1]
Insured Swaps [Member] | Other Assets [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative Assets, Not designated, Fair Value	0	[1]	0	[1]
Non Insured Credit Default Swaps [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative notional amount	0		0
Non Insured Credit Default Swaps [Member] | Derivative Liabilities [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative Liabilities, Not designated, Fair Value	0	[1]	0	[1]
Non Insured Credit Default Swaps [Member] | Other Assets [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative Assets, Not designated, Fair Value	0	[1]	0	[1]
Non Insured Credit Default Swaps V I E [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative notional amount	0		0
Non Insured Credit Default Swaps V I E [Member] | Derivative Liabilities V I E [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative Liabilities, Not designated, Fair Value	0	[1]	0	[1]
Non Insured Credit Default Swaps V I E [Member] | Other Assets V I E [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative Assets, Not designated, Fair Value	0	[1]	0	[1]
Interest Rate Swaps V I E [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative notional amount	0		0
Interest Rate Swaps V I E [Member] | Derivative Liabilities V I E [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative Liabilities, Not designated, Fair Value	0	[1]	0	[1]
Interest Rate Swaps V I E [Member] | Other Assets V I E [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative Assets, Not designated, Fair Value	0	[1]	0	[1]
Interest Rate Swaps Embedded [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative notional amount	497		496
Interest Rate Swaps Embedded [Member] | Medium Term Notes [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative Assets, Not designated, Fair Value	10	[1]	9	[1]
Derivative Liabilities, Not designated, Fair Value	(21)	[1]	(19)	[1]
Currency Swap [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative notional amount	0		0
Currency Swap [Member] | Derivative Liabilities [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative Liabilities, Not designated, Fair Value	0	[1]	0	[1]
Currency Swap [Member] | Other Assets [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative Assets, Not designated, Fair Value	0	[1]	0	[1]
Currency Swaps Vie [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative notional amount	96		99
Currency Swaps Vie [Member] | Derivative Liabilities V I E [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative Liabilities, Not designated, Fair Value	(5)	[1]	(11)	[1]
Currency Swaps Vie [Member] | Other Assets V I E [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative Assets, Not designated, Fair Value	0	[1]	0	[1]
All Other [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative notional amount	83		36
All Other [Member] | Derivative Liabilities [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative Liabilities, Not designated, Fair Value	(31)	[1]	(15)	[1]
All Other [Member] | Other Assets [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative Assets, Not designated, Fair Value	0	[1]	0	[1]
All Other V I E [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative notional amount	263		280
All Other V I E [Member] | Derivative Liabilities V I E [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative Liabilities, Not designated, Fair Value	0	[1]	0	[1]
All Other V I E [Member] | Other Assets V I E [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative Assets, Not designated, Fair Value	0	[1]	0	[1]
All Other Embedded [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative notional amount	11		11
All Other Embedded [Member] | Derivative Liabilities Other Investments [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative Liabilities, Not designated, Fair Value	0	[1]	0	[1]
All Other Embedded [Member] | Derivative Assets Other Investments [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative Assets, Not designated, Fair Value	$ 0	[1]	$ 0	[1]

[1] In accordance with the accounting guidance for derivative instruments and hedging activities, the balance sheet location of the Company’s embedded derivative instruments is determinedby the location of the related host contract.