Loans - Consumer, Excluding Credit Card Loan Portfolio, Delinquency Statistics Junior Lien Home Equity Loans (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2019	Dec. 31, 2018	Sep. 30, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 928,887	$ 969,415	$ 947,651
Consumer, excluding credit card
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	331,809	373,637	$ 375,958
Consumer, excluding credit card \| Total
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 24,954	$ 28,340
Total 30 plus day delinquency rate	2.23%	2.57%
Consumer, excluding credit card \| Total \| Senior lien
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of senior liens to total financing receivables	37.00%
Consumer, excluding credit card \| Total \| Junior lien
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 15,735	$ 17,924
Total 30 plus day delinquency rate	1.72%	2.00%
Consumer, excluding credit card \| HELOANs \| Junior lien
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 827	$ 1,030
Total 30 plus day delinquency rate	2.42%	2.82%
Consumer, excluding credit card \| HELOCs, Within the revolving period \| HELOCs \| Junior lien
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 5,625	$ 5,608
Total 30 plus day delinquency rate	0.37%	0.25%
Open-ended revolving period	10 years
Consumer, excluding credit card \| HELOCs, Beyond the revolving period \| HELOCs \| Junior lien
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 9,283	$ 11,286
Total 30 plus day delinquency rate	2.47%	2.80%
Amortization period	20 years

After conversion from a revolving loan, the home equity line of credit new loan amortization period.

No definition available.

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- Definition

In general, the period of time that home equity lines of credit are open-ended revolving loans.

+ References

No definition available.

+ Details

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Data Type:	xbrli:durationItemType
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- Definition

This item represents the percentage of loans 30 plus days past due as compared to total retained loans.

+ References

No definition available.

+ Details

Name:	jpm_PercentageOfLoansThirtyPlusDaysPastDueToTotalRetainedLoans
Namespace Prefix:	jpm_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The percentage of the financing receivables that consists of senior liens.

+ References

No definition available.

+ Details

Name:	jpm_PercentageOfSeniorLiensToTotalFinancingReceivables
Namespace Prefix:	jpm_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=118952595&loc=d3e4428-111522

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5074-111524

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=jpm_ConsumerExcludingCreditCardLoanPortfolioSegmentMember
Namespace Prefix:
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- Details

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- Details

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Balance Type:
Period Type:

- Details

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- Details

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- Details

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- Details

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