Variable Interest Entities - Securitization Activity (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Residential mortgage-backed securities \| Level 2
All cash flows during the period:
Proceeds from new securitizations	$ 2,400	$ 1,400
Residential mortgage-backed securities \| Level 3
All cash flows during the period:
Proceeds from new securitizations	185
Mortgage-backed securities, Commercial \| Level 2
All cash flows during the period:
Proceeds from new securitizations	11,400	11,300	5,700
Mortgage-backed securities, Commercial \| Level 3
All cash flows during the period:
Proceeds from new securitizations	130
Mortgage-backed securities, Commercial \| Cash
All cash flows during the period:
Proceeds from new securitizations		207
Mortgage-backed securities, Commercial \| Cash \| Level 2
All cash flows during the period:
Proceeds from new securitizations	568
Variable Interest Entity (VIE) or Potential VIE, Information Unavailability \| Residential mortgage-backed securities
Securitization activity [Abstract]
Principal securitized	2,558	1,404	0
All cash flows during the period:
Proceeds from new securitizations	2,569	1,410	0
Servicing fees collected	557	576	662
Purchases of previously transferred financial assets (or the underlying collateral)	121	294	222
Cash flows received on interests	179	156	185
Weighted-average life (in years)	5 years 10 months 24 days	3 years 10 months 24 days
Discount rate	3.40%	2.50%
Variable Interest Entity (VIE) or Potential VIE, Information Unavailability \| Mortgage-backed securities, Commercial
Securitization activity [Abstract]
Principal securitized	11,911	11,318	5,421
All cash flows during the period:
Proceeds from new securitizations	12,079	11,507	5,705
Servicing fees collected	4	5	4
Purchases of previously transferred financial assets (or the underlying collateral)	0	0	0
Cash flows received on interests	$ 578	$ 325	$ 163
Weighted-average life (in years)	6 years 6 months	8 years 3 months 18 days	8 years 9 months 18 days
Discount rate	4.80%	3.20%	3.60%

The principal amount of financial assets transferred during the period in securitizations accounted for as sales.

No definition available.

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

- Details

Name:	jpm_SecuritizationActivityAbstract
Namespace Prefix:	jpm_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Discount rate which is used to value residual cash flows generated by financial assets of the securitization, asset-backed financing arrangement, or similar transfer for initial fair value measurement.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 20

-Section 50

-Paragraph 3

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=13989330&loc=d3e107207-111719

+ Details

Name:	us-gaap_AssumptionForFairValueOnSecuritizationDateOfInterestsContinuedToBeHeldByTransferorServicingAssetsOrLiabilitiesDiscountRate
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_CashFlowsBetweenTransfereeAndTransferorAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Cash Flows between a transferor and a transferee attributable to newly transferred assets related to either a securitization, asset-backed financing arrangement, or similar transfer in which the transferor has continuing involvement with the transferred financial assets underlying the transaction (including, but not limited to, servicing, recourse, and restrictions on transferor's interests in the transferred financial assets).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 20

-Section 50

-Paragraph 3

-Subparagraph b

-URI http://asc.fasb.org/extlink&oid=13989330&loc=d3e107207-111719

+ Details

Name:	us-gaap_CashFlowsBetweenTransfereeAndTransferorProceedsFromNewTransfers
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Cash Flows between a transferor and a transferee attributable to purchases of previously transferred financial assets (or its underlying collateral) related to a securitization, asset-backed financing arrangement, or similar transfer in which the transferor has continuing involvement with the transferred financial assets underlying the transaction (including, but not limited to, servicing, recourse, and restrictions on transferor's interests in the transferred financial assets).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 20

-Section 50

-Paragraph 3

-Subparagraph b

-URI http://asc.fasb.org/extlink&oid=13989330&loc=d3e107207-111719

+ Details

Name:	us-gaap_CashFlowsBetweenTransfereeAndTransferorPurchasesOfPreviouslyTransferredFinancialAssets
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Cash flows between transferor and a transferee attributable to the transferor's interests related to a securitization, asset-backed financing arrangement, or similar transfer in which the transferor will have continuing involvement with the transferred financial assets underlying the transaction (including, but not limited to, servicing, recourse, and restrictions on transferor's interests in the transferred financial assets).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 20

-Section 50

-Paragraph 3

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=13989330&loc=d3e107207-111719

+ Details

Name:	us-gaap_CashFlowsBetweenTransfereeAndTransferorReceiptsOnInterestsThatContinueToBeHeldOther
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Cash Flows between a transferee and a transferor attributable to servicing fees related to a securitization, asset-backed financing arrangement, or similar transfer in which the transferor has continuing involvement with the transferred financial assets underlying the transaction (including, but not limited to, servicing, recourse, and restrictions on transferor's interests in the transferred financial assets).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 20

-Section 50

-Paragraph 3

-Subparagraph d

-URI http://asc.fasb.org/extlink&oid=13989330&loc=d3e107207-111719

+ Details

Name:	us-gaap_CashFlowsBetweenTransfereeAndTransferorServicingFees
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Weighted average life of securitized assets for initial fair value measurement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 20

-Section 50

-Paragraph 3

-Subparagraph (c)(2)

-URI http://asc.fasb.org/extlink&oid=13989330&loc=d3e107207-111719

+ Details

Name:	us-gaap_FairValueAssumptionDateOfSecuritizationOrAssetBackedFinancingArrangementTransferorsContinuingInvolvementServicingAssetsOrLiabilitiesWeightedAverageLife
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_UnderlyingAssetClassAxis=us-gaap_CommercialMortgageBackedSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_UnderlyingAssetClassAxis=us-gaap_ResidentialMortgageBackedSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableInterestEntitiesByClassificationOfEntityAxis=us-gaap_VariableInterestEntityVIEOrPotentialVIEInformationUnavailabilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: