Derivative Financial Instruments (Details) (USD $) In Millions	Jun. 30, 2011	Dec. 31, 2010
Impact of Derivatives on Consolidated Balance Sheet
Total derivative assets	$ 4,001	$ 3,219
Total derivative liabilities	(2,909)	(1,954)
Net total derivatives	1,092	1,265
Non-designated [Member]
Impact of Derivatives on Consolidated Balance Sheet
Total derivative assets	261	327
Total derivative liabilities	2,682	(1,664)
Net total derivatives	(2,421)	(1,337)
Non-designated [Member] \| Interest rate swaps [Member]
Impact of Derivatives on Consolidated Balance Sheet
Interest Rate Assets, Trading	158	200
Interest Rate Liabilities, Trading	(291)	(348)
Non-designated [Member] \| Floor Income contracts [Member]
Impact of Derivatives on Consolidated Balance Sheet
Interest Rate Liabilities, Trading	(2,390)	(1,315)
Non-designated [Member] \| Cross currency interest rate swaps [Member]
Impact of Derivatives on Consolidated Balance Sheet
Foreign Currency Assets, Trading	100	101
Foreign Currency Liabilities, Trading	(1)	0
Non-designated [Member] \| Other Contract [Member]
Impact of Derivatives on Consolidated Balance Sheet
Interest Rate Assets, Trading	3	26
Interest Rate Liabilities, Trading	0	(1)
Cash Flow Hedging [Member]
Impact of Derivatives on Consolidated Balance Sheet
Total derivative assets	0	0
Total derivative liabilities	(43)	(75)
Net total derivatives	(43)	(75)
Cash Flow Hedging [Member] \| Interest rate swaps [Member]
Impact of Derivatives on Consolidated Balance Sheet
Interest Rate Assets, Cash Flow	0	0
Interest Rate Liabilities, Cash Flow	(43)	(75)
Cash Flow Hedging [Member] \| Floor Income contracts [Member]
Impact of Derivatives on Consolidated Balance Sheet
Interest Rate Liabilities, Cash Flow	0	0
Cash Flow Hedging [Member] \| Cross currency interest rate swaps [Member]
Impact of Derivatives on Consolidated Balance Sheet
Foreign Currency Assets, Cash Flow	0	0
Foreign Currency Liabilities, Cash Flow	0	0
Cash Flow Hedging [Member] \| Other Contract [Member]
Impact of Derivatives on Consolidated Balance Sheet
Interest Rate Assets, Cash Flow	0	0
Interest Rate Liabilities, Cash Flow	0	0
Fair Value Hedging [Member]
Impact of Derivatives on Consolidated Balance Sheet
Total derivative assets	3,740	2,892
Total derivative liabilities	(184)	(215)
Net total derivatives	3,556	2,677
Fair Value Hedging [Member] \| Interest rate swaps [Member]
Impact of Derivatives on Consolidated Balance Sheet
Interest Rate Assets, Fair Value	972	967
Interest Rate Liabilities, Fair Value	0	0
Fair Value Hedging [Member] \| Floor Income contracts [Member]
Impact of Derivatives on Consolidated Balance Sheet
Interest Rate Liabilities, Fair Value	0	0
Fair Value Hedging [Member] \| Cross currency interest rate swaps [Member]
Impact of Derivatives on Consolidated Balance Sheet
Foreign Currency Assets, Fair Value	2,768	1,925
Foreign Currency Liabilities, Fair Value	(184)	(215)
Fair Value Hedging [Member] \| Other Contract [Member]
Impact of Derivatives on Consolidated Balance Sheet
Interest Rate Assets, Fair Value	0	0
Interest Rate Liabilities, Fair Value	0	0
Interest rate swaps [Member]
Impact of Derivatives on Consolidated Balance Sheet
Interest Rate Assets, Total	1,130	1,167
Interest Rate Liabilities, Total	(334)	(423)
Floor Income contracts [Member]
Impact of Derivatives on Consolidated Balance Sheet
Interest Rate Liabilities, Total	(2,390)	(1,315)
Cross currency interest rate swaps [Member]
Impact of Derivatives on Consolidated Balance Sheet
Foreign Currency Assets, Total	2,868	2,026
Foreign Currency Liabilities, Total	(185)	(215)
Other Contract [Member]
Impact of Derivatives on Consolidated Balance Sheet
Interest Rate Assets, Total	3	26
Interest Rate Liabilities, Total	$ 0	$ (1)

Impact of Derivatives on Consolidated Balance Sheet.

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Fair value of derivative asset, presented on a gross basis even when the derivative instrument is subject to master netting arrangements and qualifies for net presentation in the statement of financial position.

+ References

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-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
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Fair value of derivative liability, presented on a gross basis even when the derivative instrument is subject to master netting arrangements and qualifies for net presentation in the statement of financial position.

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Fair value as of the balance sheet date of the assets less the liabilities of a derivative or group of derivatives.

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Fair value as of the balance sheet date of all foreign currency derivative assets designated as cash flow hedging instruments.

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Fair value as of the balance sheet date of all foreign currency derivative liabilities designated as cash flow hedging instruments.

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Fair value as of the balance sheet date of foreign currency derivative assets, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as assets on the balance sheet.

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Fair value as of the balance sheet date of interest rate derivative liabilities, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as liabilities on the balance sheet.

+ References

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