Derivatives and Hedging Activities (Details Textuals) - USD ($) shares in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Dec. 31, 2015
Derivatives and Hedging Activities (Textuals) [Abstract]
Net reduction in interest expense on long term debt and other	$ 59,000,000	$ 71,000,000	$ 118,000,000	$ 140,000,000
Derivative asset not offset					$ 8
Shares held in equity investment sold	0.0		0.0
Margin On Interest Rate Swap Not Netted	$ 159,000,000		$ 159,000,000		149,000,000
Derivative [Line Items]
Equity investment	1,000,000		1,000,000		1,000,000
Effective portion of gain (loss) on hedges	135,000,000	(34,000,000)	43,000,000	161,000,000
Net hedge ineffectiveness	0
Derivative Instruments, Gain (Loss) Recognized in Income, Net		87,000,000		381,000,000
Not Sold Or Repledged [Member]
Derivative [Line Items]
Securities received as collateral	30,000,000		30,000,000		0
Risk Exposure Low [Member]
Derivative [Line Items]
Total derivative assets, net	583,000,000		583,000,000
Other Expense [Member]
Derivative [Line Items]
Gain (Loss) in Changes of Fair Value of Derivatives not designated as hedges	6,000,000	8,000,000	8,000,000	105,000,000
Gain on embedded derivatives	0	$ 4,000,000	6,000,000	$ 3,000,000
ICBC [Member] | Estimate of Fair Value, Fair Value Disclosure [Member]
Derivative [Line Items]
Equity investment	0		0
Fair Value Hedges [Member]
Derivative [Line Items]
Notional amount of long-term debt	20,250,000,000		20,250,000,000		$ 18,800,000,000
Net Investment Hedging [Member] | Other Expense [Member]
Derivative [Line Items]
Amount reclassified from AOCI into income	0
Net hedge ineffectiveness	0
Net Investment Hedging [Member] | Net Investment Hedging [Member] | Other Expense [Member]
Derivative [Line Items]
Amount reclassified from AOCI into income	0
Credit Valuation Adjustment [Member]
Derivative [Line Items]
Notional amount of long-term debt	$ 0		$ 0