Fair value measurement - Credit Adjustments Reflected on Balance Sheet (Details) - USD ($) $ in Millions	Sep. 30, 2015	Dec. 31, 2014
Credit adjustments [Abstract]
Derivative receivables balance	$ 68,668	$ 78,975
Derivative payables, net	57,140	71,116
Derivative CVA	(2,279)	(2,674)
Derivatives and Structured notes DVA and FVA	(437)	(380)
Structured notes balance	51,887	53,772
Derivatives DVA	822	714
Plain Vanilla Financial Instruments
Credit adjustments [Abstract]
Structured notes	1,700	943
Structured Finance
Credit adjustments [Abstract]
Derivatives and Structured notes DVA and FVA	2,355	1,152
Derivatives DVA	$ 1,900	$ 1,400

Credit adjustments.

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- Definition

Amount of credit risk valuation adjustment to derivative liabilities to properly reflect the credit quality of the entity, and amount of funding valuation adjustment to properly reflect the funding cost or benefit that a relevant market participant would consider in the transfer of an OTC derivative or structured note.

+ References

No definition available.

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This item represents disclosure of all significant concentrations of credit risk arising from structured notes, whether from an individual counterparty or groups of counterparties, net of derivative valuation adjustments.

+ References

No definition available.

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- Definition

Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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Amount of credit risk valuation adjustment to derivative assets to properly reflect the credit quality of the counterparties.

+ References

No definition available.

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Amount of credit risk valuation adjustment to derivative liabilities to properly reflect the credit quality of the entity.

+ References

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

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