Pension and Other Postretirement Employee Benefit Plans - Weighted-Average Assumptions Net Periodic Benefit Costs (Details)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
U.S. defined benefit pension plans
Weighted-average assumptions used to determine net periodic benefit costs
Discount rate	5.00%	3.90%	4.60%
Expected long-term rate of return on plan assets	7.00%	7.50%	7.50%
Non-U.S. defined benefit pension plans \| Minimum
Weighted-average assumptions used to determine net periodic benefit costs
Discount rate	1.10%	1.40%	1.50%
Expected long-term rate of return on plan assets	1.20%	2.40%	2.50%
Non-U.S. defined benefit pension plans \| Maximum
Weighted-average assumptions used to determine net periodic benefit costs
Discount rate	4.40%	4.40%	4.80%
Expected long-term rate of return on plan assets	5.30%	4.90%	4.60%
U.S. OPEB plans
Weighted-average assumptions used to determine net periodic benefit costs
Discount rate	4.90%	3.90%	4.70%
Expected long-term rate of return on plan assets	6.25%	6.25%	6.25%
Health care cost trend rate:
Assumed for next year	6.50%	7.00%	7.00%
Ultimate	5.00%	5.00%	5.00%
Year when rate will reach ultimate	2017	2017	2017
Pension and other postretirement employee benefit plans, U.S.
Weighted-average assumptions used to determine net periodic benefit costs
Rate of compensation increase	3.50%	4.00%	4.00%
Health care cost trend rate:
Ultimate	5.00%
Year when rate will reach ultimate	2017
Non-U.S. pension and other postretirement employee benefit plans \| Minimum
Weighted-average assumptions used to determine net periodic benefit costs
Rate of compensation increase	2.75%	2.75%	2.75%
Non-U.S. pension and other postretirement employee benefit plans \| Maximum
Weighted-average assumptions used to determine net periodic benefit costs
Rate of compensation increase	4.60%	4.10%	4.20%

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

The interest rate used to adjust for the time value of money.

+ References

+ Details

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

- Definition

An assumption as to the rate of return on plan assets reflecting the average rate of earnings expected on the funds invested or to be invested to provide for the benefits included in the benefit obligation.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 30

-Glossary Expected Long-Term Rate of Return on Plan Assets

-URI http://asc.fasb.org/extlink&oid=6512013

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (k)(3)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

+ Details

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

- Definition

Expected rate of compensation increases (for pay-related plans).

+ References

+ Details

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

- Definition

The assumed health care cost trend rate for the next year used to measure the expected cost of benefits covered by the plan (gross eligible charges). This is based upon the annual rate of change in the cost of health care benefits currently provided by the postretirement benefit plan, due to factors other than changes in the composition of the plan population by age and dependency status.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (l)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Health Care Cost Trend Rate

-URI http://asc.fasb.org/extlink&oid=6514820

+ Details

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

- Definition

The ultimate trend rate for health care costs.

+ References

+ Details

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

- Details

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

- Definition

Year the ultimate health care cost trend rate is expected to be reached, in CCYY format.

+ References

+ Details

Name:	us-gaap_DefinedBenefitPlanYearThatRateReachesUltimateTrendRate
Namespace Prefix:	us-gaap_
Data Type:	xbrli:gYearItemType
Balance Type:	na
Period Type:	instant

- Details

Name:	us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis=jpm_ForeignPensionPlansAndOtherForeignPostretirementBenefitPlansMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis=jpm_UsPensionPlansAndOtherUsPostretirementEmployeeBenefitPlansMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis=us-gaap_ForeignPensionPlansDefinedBenefitMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis=us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis=us-gaap_UnitedStatesPostretirementBenefitPlansOfUSEntityDefinedBenefitMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: