Business Segments (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		12 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2011	Dec. 31, 2012
Business and Segment Description [Abstract]
Number of JPMorgan Chase & Co business segments	4
Segment results and reconciliation
Noninterest Income	$ 14,189	$ 14,386
Interest Income (Expense), Net	10,933	11,666
Total net revenue	25,122	26,052
Provision for credit losses	617	726
Noninterest expense	15,423	18,345
Income before income tax expense	9,082	6,981
Income tax expense / (benefit)	2,553	2,057
Net income/(loss)	6,529	4,924
Average common equity	194,733	177,711
Total assets	2,389,349	2,320,164		2,359,141
Return on average common equity	13.00%	11.00%
Overhead ratio	61.00%	70.00%
Consumer & Community Banking
Segment results and reconciliation
Noninterest Income	4,406	4,975	4,975
Interest Income (Expense), Net	7,209	7,388	7,388
Total net revenue	11,615	12,363	12,363
Provision for credit losses	549	642	642
Noninterest expense	6,790	7,038	7,038
Income before income tax expense	4,276	4,683	4,683
Income tax expense / (benefit)	1,690	1,747	1,747
Net income/(loss)	2,586	2,936	2,936
Average common equity	46,000	43,000	43,000
Total assets	458,902	469,084		469,084
Return on average common equity	23.00%	27.00%	27.00%
Overhead ratio	58.00%	57.00%	57.00%
Corporate & Investment Bank
Segment results and reconciliation
Noninterest Income	7,357	6,488
Interest Income (Expense), Net	2,783	2,850
Total net revenue	10,140	9,338
Provision for credit losses	11	(3)
Noninterest expense	6,111	6,211
Income before income tax expense	4,018	3,130
Income tax expense / (benefit)	1,408	1,097
Net income/(loss)	2,610	2,033
Average common equity	56,500	47,500
Total assets	872,259	879,691
Return on average common equity	19.00%	17.00%
Overhead ratio	60.00%	67.00%
Commercial Banking
Segment results and reconciliation
Noninterest Income	535	557
Interest Income (Expense), Net	1,138	1,100
Total net revenue	1,673	1,657
Provision for credit losses	39	77
Noninterest expense	644	598
Income before income tax expense	990	982
Income tax expense / (benefit)	394	391
Net income/(loss)	596	591
Average common equity	13,500	9,500
Total assets	184,689	161,741
Return on average common equity	18.00%	25.00%
Overhead ratio	38.00%	36.00%
Asset Management
Segment results and reconciliation
Noninterest Income	2,094	1,887
Interest Income (Expense), Net	559	483
Total net revenue	2,653	2,370
Provision for credit losses	21	19
Noninterest expense	1,876	1,729
Income before income tax expense	756	622
Income tax expense / (benefit)	269	236
Net income/(loss)	487	386
Average common equity	9,000	7,000
Total assets	109,734	96,385
Return on average common equity	22.00%	22.00%
Overhead ratio	71.00%	73.00%
Corporate/Private Equity
Segment results and reconciliation
Noninterest Income	361	1,013
Interest Income (Expense), Net	(594)	16
Total net revenue	(233)	1,029
Provision for credit losses	(3)	(9)
Noninterest expense	2	2,769
Income before income tax expense	(232)	(1,731)
Income tax expense / (benefit)	(482)	(709)
Net income/(loss)	250	(1,022)
Average common equity	69,733	70,711
Total assets	763,765	713,263
Reconciling Items
Segment results and reconciliation
Noninterest Income	(564)	(534)
Interest Income (Expense), Net	(162)	(171)
Total net revenue	(726)	(705)
Provision for credit losses	0	0
Noninterest expense	0	0
Income before income tax expense	(726)	(705)
Income tax expense / (benefit)	(726)	(705)
Net income/(loss)	0	0
Average common equity	$ 0	$ 0