Derivative Instruments - Impact on Statements of Income, Cash Flow Hedges (Details 2b) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2012	Mar. 31, 2011
Cash flow hedge gains and losses [Abstract]
Recognition of losses related to cash flow hedges in Income	$ 14
Maximum length of time hedged in forecasted transactions	9 years
Interest rate contract
Cash flow hedge gains and losses [Abstract]
Derivatives - effective portion reclassified from AOCI to income	21	94
Derivatives - effective portion recorded in OCI	(120)	(31)
Total change in OCI for period	(141)	(125)
Foreign exchange
Cash flow hedge gains and losses [Abstract]
Derivatives - effective portion reclassified from AOCI to income	(1)	22
Derivatives - effective portion recorded in OCI	79	18
Total change in OCI for period	80	(4)
Cash Flow Hedging [Member]
Cash flow hedge gains and losses [Abstract]
Hedge ineffectiveness recorded directly in income	5	3
Total income statement impact	25	119
Cash Flow Hedging [Member] \| Interest rate contract
Cash flow hedge gains and losses [Abstract]
Hedge ineffectiveness recorded directly in income	5	3
Total income statement impact	26	97
Cash Flow Hedging [Member] \| Foreign exchange
Cash flow hedge gains and losses [Abstract]
Hedge ineffectiveness recorded directly in income	0	0
Total income statement impact	(1)	22
Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member]
Cash flow hedge gains and losses [Abstract]
Derivatives - effective portion reclassified from AOCI to income	20	116
Derivatives - effective portion recorded in OCI	(41)	(13)
Total change in OCI for period	$ (61)	$ (129)

The portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments representing (a) the amount of the hedge ineffectiveness and (b) the amount, if any, excluded from the assessment of hedge effectiveness.

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The amount of net gains and losses recognized in income during the period on derivative instruments designated and qualifying as hedging instruments in fair value hedges and related hedged items designated and qualifying in fair value hedges, on derivative instruments designated and qualifying as hedging instruments in cash flow hedges, and on derivative instruments not designated as hedging instruments.

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- Definition

Pre tax change in accumulated gains and losses from derivative instruments designated and qualifying as the effective portion of cash flow hedges, net of reclassifications into earnings during the period. A cash flow hedge is a hedge of the exposure to variability in the cash flows of a recognized asset or liability or a forecasted transaction that is attributable to a particular risk. Includes an entity's share of an equity investee's increase or decrease in deferred hedging gains or losses. While for technical reasons this element has no balance attribute, the default assumption is a credit balance consistent with its label.

+ References

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-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

-Number 51

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+ Details

- Definition

Pre tax reclassification adjustment for accumulated gains and losses from derivative instrument designated and qualifying as the effective portion of cash flow hedges included in accumulated comprehensive income that was realized in net income during the period. A cash flow hedge is a hedge of the exposure to variability in the cash flows of a recognized asset or liability or a forecasted transaction that is attributable to a particular risk.

+ References

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-Glossary Reclassification Adjustments

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+ Details

- Definition

Pre tax change in accumulated gains and losses from derivative instrument designated and qualifying as the effective portion of cash flow hedges. A cash flow hedge is a hedge of the exposure to variability in the cash flows of a recognized asset or liability or a forecasted transaction that is attributable to a particular risk. Includes an entity's share of an equity investee's Increase or Decrease in deferred hedging gains or losses.

+ References

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