Fair Value Measurement - Impact of Credit Adjustments (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Credit and funding adjustments:
Derivatives CVA	$ 66	$ 245	$ 223	$ 715
Derivatives FVA	$ 88	$ (222)	$ 102	$ (289)

For debit valuation adjustments ("DVA") and funding valuation adjustments ("FVA"), amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

No definition available.

Name:	jpm_DerivativeGainLossonDerivativeNetDVAandFVA
Namespace Prefix:	jpm_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration