Variable interest entities - Consolidated VIE Assets and Liabilities (Details) - USD ($) $ in Millions		Sep. 30, 2015		Dec. 31, 2014		Sep. 30, 2014
Information on assets and liabilities related to VIEs that are consolidated by the Firm [Abstract]
Trading assets		$ 361,708		$ 398,988
Loans		809,457		757,336
Other		103,381		102,597
Total assets		2,417,121	[1]	2,572,773	[1]	$ 2,526,655
Beneficial interests issued by consolidated VIEs		48,733		52,362
Total liabilities	[1]	2,171,393		2,341,046
VIEs consolidated by the Firm
Information on assets and liabilities related to VIEs that are consolidated by the Firm [Abstract]
Loans		69,100		68,900
Other		2,100		1,800
Total assets		75,400		79,800
Beneficial interests issued by consolidated VIEs		48,700		52,400
Other		800		900
Total liabilities		49,500		53,300
VIEs consolidated by the Firm | Long-term beneficial interests
Information on assets and liabilities related to VIEs that are consolidated by the Firm [Abstract]
Beneficial interests issued by consolidated VIEs		33,200		35,400
VIEs consolidated by the Firm | Long-term beneficial interests maturities under 1 year
Information on assets and liabilities related to VIEs that are consolidated by the Firm [Abstract]
Beneficial interests issued by consolidated VIEs		5,000
VIEs consolidated by the Firm | Long-term beneficial interests maturities between 1 and 5 years
Information on assets and liabilities related to VIEs that are consolidated by the Firm [Abstract]
Beneficial interests issued by consolidated VIEs		23,800
VIEs consolidated by the Firm | Long-term beneficial interests maturities over 5 years
Information on assets and liabilities related to VIEs that are consolidated by the Firm [Abstract]
Beneficial interests issued by consolidated VIEs		4,400
VIEs consolidated by the Firm | Debt and equity securities
Information on assets and liabilities related to VIEs that are consolidated by the Firm [Abstract]
Trading assets		4,200		9,100
VIEs consolidated by the Firm | Firm-sponsored credit card trusts
Information on assets and liabilities related to VIEs that are consolidated by the Firm [Abstract]
Loans		46,700		48,300
Other		700		700
Total assets		47,400		49,000
Beneficial interests issued by consolidated VIEs		30,100		31,200
Other		0		0
Total liabilities		30,100		31,200
VIEs consolidated by the Firm | Firm-sponsored credit card trusts | Debt and equity securities
Information on assets and liabilities related to VIEs that are consolidated by the Firm [Abstract]
Trading assets		0		0
VIEs consolidated by the Firm | Firm-administered multi-seller conduits
Information on assets and liabilities related to VIEs that are consolidated by the Firm [Abstract]
Loans		19,000		17,700
Other		0		100
Total assets		19,000		17,800
Beneficial interests issued by consolidated VIEs		13,000		12,000
Other		0		0
Total liabilities		13,000		12,000
VIEs consolidated by the Firm | Firm-administered multi-seller conduits | Debt and equity securities
Information on assets and liabilities related to VIEs that are consolidated by the Firm [Abstract]
Trading assets		0		0
VIEs consolidated by the Firm | Municipal bond vehicles
Information on assets and liabilities related to VIEs that are consolidated by the Firm [Abstract]
Loans		0		0
Other		0		0
Total assets		2,700		5,300
Beneficial interests issued by consolidated VIEs		2,600		4,900
Other		0		0
Total liabilities		2,600		4,900
VIEs consolidated by the Firm | Municipal bond vehicles | Debt and equity securities
Information on assets and liabilities related to VIEs that are consolidated by the Firm [Abstract]
Trading assets		2,700		5,300
VIEs consolidated by the Firm | Mortgage securitization entities
Information on assets and liabilities related to VIEs that are consolidated by the Firm [Abstract]
Loans		1,400		700
Other		0		0
Total assets		2,600		4,000
Beneficial interests issued by consolidated VIEs		900		2,100
Other		700		800
Total liabilities		1,600		2,900
VIEs consolidated by the Firm | Mortgage securitization entities | Debt and equity securities
Information on assets and liabilities related to VIEs that are consolidated by the Firm [Abstract]
Trading assets		1,200		3,300
VIEs consolidated by the Firm | Student loan securitization entities
Information on assets and liabilities related to VIEs that are consolidated by the Firm [Abstract]
Loans		2,000		2,200
Other		100		0
Total assets		2,200		2,400
Beneficial interests issued by consolidated VIEs		1,900		2,100
Other		0		0
Total liabilities		1,900		2,100
VIEs consolidated by the Firm | Student loan securitization entities | Debt and equity securities
Information on assets and liabilities related to VIEs that are consolidated by the Firm [Abstract]
Trading assets		100		200
VIEs consolidated by the Firm | Other
Information on assets and liabilities related to VIEs that are consolidated by the Firm [Abstract]
Loans		0		0
Other		1,300		1,000
Total assets		1,500		1,300
Beneficial interests issued by consolidated VIEs		200		100
Other		100		100
Total liabilities		300		200
VIEs consolidated by the Firm | Other | Debt and equity securities
Information on assets and liabilities related to VIEs that are consolidated by the Firm [Abstract]
Trading assets		$ 200		$ 300

[1] The following table presents information on assets and liabilities related to VIEs that are consolidated by the Firm at September 30, 2015, and December 31, 2014. The difference between total VIE assets and liabilities represents the Firm’s interests in those entities, which were eliminated in consolidation.(in millions)Sep 30, 2015 Dec 31, 2014Assets Trading assets$4,237 $9,090Loans69,119 68,880All other assets2,109 1,815Total assets$75,465 $79,785Liabilities Beneficial interests issued by consolidated variable interest entities$48,733 $52,362All other liabilities821 949Total liabilities$49,554 $53,311The assets of the consolidated VIEs are used to settle the liabilities of those entities. The holders of the beneficial interests do not have recourse to the general credit of JPMorgan Chase. At both September 30, 2015, and December 31, 2014, the Firm provided limited program-wide credit enhancement of $2.0 billion related to its Firm-administered multi-seller conduits, which are eliminated in consolidation. For further discussion, see Note 15.