Regulatory Capital (Details) - USD ($) $ in Millions		9 Months Ended	21 Months Ended
	Jan. 01, 2020	Sep. 30, 2021	Sep. 30, 2021	Dec. 31, 2020
Cumulative effect of a change in accounting principle
Regulatory capital, assets and risk based ratios - supplemental information [Abstract]
Amount excluded from capital measures of the Firm		$ 3,300
Decrease to retained earnings	$ 2,700
Cumulative effect of a change in accounting principle | Excluding PCD Loans
Regulatory capital, assets and risk based ratios - supplemental information [Abstract]
Increase in allowance for credit losses, excluding allowances on PCD loans			$ 1,900
JPMorgan Chase & Co.
Leverage-based capital metrics:
Adjusted average assets		$ 3,675,803	$ 3,675,803	$ 3,353,319
Tier 1 leverage ratio		0.066	0.066	0.070
Total leverage exposure		$ 4,463,904	$ 4,463,904	$ 3,401,542
SLR		0.055	0.055	0.069
Basel III Standardized | JPMorgan Chase & Co.
Risk-based capital metrics:
CET1 capital		$ 209,917	$ 209,917	$ 205,078
Tier 1 capital		244,207	244,207	234,844
Total capital		274,994	274,994	269,923
Risk-weighted assets		$ 1,628,406	$ 1,628,406	$ 1,560,609
CET1 capital ratio		12.90%	12.90%	13.10%
Tier 1 capital ratio		0.150	0.150	0.150
Total capital ratio		0.169	0.169	0.173
Basel III Advanced | JPMorgan Chase & Co.
Risk-based capital metrics:
CET1 capital		$ 209,917	$ 209,917	$ 205,078
Tier 1 capital		244,207	244,207	234,844
Total capital		264,469	264,469	257,228
Risk-weighted assets		$ 1,544,512	$ 1,544,512	$ 1,484,431
CET1 capital ratio		13.60%	13.60%	13.80%
Tier 1 capital ratio		0.158	0.158	0.158
Total capital ratio		0.171	0.171	0.173
Bank Holding Companies | Basel III
Well capitalized risk-based ratios
Tier 1 capital		0.060	0.060	0.060
Total capital		0.100	0.100	0.100
Minimum leverage-based capital ratios
Tier 1 leverage		0.040	0.040	0.040
SLR		5.00%	5.00%	5.00%
Regulatory capital, assets and risk based ratios - supplemental information [Abstract]
GSIB surcharge		3.50%	3.50%	3.50%
Countercyclical buffer		0	0	0
SLR, minimum requirement		3.00%	3.00%	3.00%
SLR, supplementary leverage buffer requirements		2.00%	2.00%	2.00%
Bank Holding Companies | Basel III Standardized
Minimum risk-based capital ratios
CET1 capital		11.30%	11.30%	11.30%
Tier 1 capital		0.128	0.128	0.128
Total capital		0.148	0.148	0.148
Regulatory capital, assets and risk based ratios - supplemental information [Abstract]
Stress capital buffer		3.30%	3.30%	3.30%
Bank Holding Companies | Basel III Advanced
Minimum risk-based capital ratios
CET1 capital		10.50%	10.50%	10.50%
Tier 1 capital		0.120	0.120	0.120
Total capital		0.140	0.140	0.140
Regulatory capital, assets and risk based ratios - supplemental information [Abstract]
Capital conservation buffer requirement		2.50%	2.50%	2.50%
Insured Depository Institutions | Basel III
Well capitalized risk-based ratios
CET1 capital		6.50%	6.50%	6.50%
Tier 1 capital		0.080	0.080	0.080
Total capital		0.100	0.100	0.100
Minimum leverage-based capital ratios
Tier 1 leverage		0.040	0.040	0.040
SLR		6.00%	6.00%	6.00%
Well capitalized leverage-based capital ratios
Tier 1 leverage		0.050	0.050	0.050
SLR		6.00%	6.00%	6.00%
Regulatory capital, assets and risk based ratios - supplemental information [Abstract]
Capital conservation buffer requirement		2.50%	2.50%	2.50%
SLR, minimum requirement		3.00%	3.00%	3.00%
SLR, supplementary leverage buffer requirements		3.00%	3.00%	3.00%
Insured Depository Institutions | Basel III Standardized
Minimum risk-based capital ratios
CET1 capital		7.00%	7.00%	7.00%
Tier 1 capital		0.085	0.085	0.085
Total capital		0.105	0.105	0.105
Insured Depository Institutions | Basel III Advanced
Minimum risk-based capital ratios
CET1 capital		7.00%	7.00%	7.00%
Tier 1 capital		0.085	0.085	0.085
Total capital		0.105	0.105	0.105
JPMorgan Chase Bank, N.A.
Leverage-based capital metrics:
Adjusted average assets		$ 3,223,098	$ 3,223,098	$ 2,970,285
Tier 1 leverage ratio		0.081	0.081	0.079
Total leverage exposure		$ 4,003,800	$ 4,003,800	$ 3,688,797
SLR		0.065	0.065	0.063
JPMorgan Chase Bank, N.A. | Basel III Standardized
Risk-based capital metrics:
CET1 capital		$ 259,990	$ 259,990	$ 234,235
Tier 1 capital		259,994	259,994	234,237
Total capital		276,303	276,303	252,045
Risk-weighted assets		$ 1,562,370	$ 1,562,370	$ 1,492,138
CET1 capital ratio		16.60%	16.60%	15.70%
Tier 1 capital ratio		0.166	0.166	0.157
Total capital ratio		0.177	0.177	0.169
JPMorgan Chase Bank, N.A. | Basel III Advanced
Risk-based capital metrics:
CET1 capital		$ 259,990	$ 259,990	$ 234,235
Tier 1 capital		259,994	259,994	234,237
Total capital		265,403	265,403	239,673
Risk-weighted assets		$ 1,396,725	$ 1,396,725	$ 1,343,185
CET1 capital ratio		18.60%	18.60%	17.40%
Tier 1 capital ratio		0.186	0.186	0.174
Total capital ratio		0.190	0.190	0.178