Loans - Wholesale RealEstate Loans, by Risk, Geography, Delinquency (Details 1) (USD $) In Millions, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011	Mar. 31, 2011
Loan credit quality and risk ratings [Line Items]
Retained loans	$ 712,898	$ 718,997	$ 675,437
Wholesale
Loan credit quality and risk ratings [Line Items]
Retained loans	283,653	278,395
Percentage of total criticized to total retained loans	3.11%	3.45%
Percentage of nonaccrual loans to total retained loans	0.68%	0.86%
Wholesale | Investment grade [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	198,704	197,070
Wholesale | Total noninvestment grade [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	84,949	81,325
Wholesale | Non Criticized [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	76,133	71,709
Wholesale | Criticized performing [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	6,875	7,218
Wholesale | Criticized total nonaccrual [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	1,941	2,398
Wholesale | Current and less than 30 days past due and still accruing [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	279,886	274,158
Wholesale | 30-89 days past due and still accruing [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	1,734	1,739
Wholesale | 90 days or more past due and still accruing [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	92	100
Wholesale | Nonaccrual [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	1,941	2,398
Wholesale | Total U.S.[Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	186,090	183,231
Wholesale | Total non-U.S.[Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	97,563	95,164
Wholesale | Commercial and industrial [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	97,089	94,215
Percentage of total criticized to total retained loans	3.21%	3.34%
Percentage of nonaccrual loans to total retained loans	0.80%	0.94%
Wholesale | Commercial and industrial [Member] | Investment grade [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	52,476	52,428
Wholesale | Commercial and industrial [Member] | Total noninvestment grade [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	44,613	41,787
Wholesale | Commercial and industrial [Member] | Non Criticized [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	41,499	38,644
Wholesale | Commercial and industrial [Member] | Criticized performing [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	2,333	2,254
Wholesale | Commercial and industrial [Member] | Criticized total nonaccrual [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	781	889
Wholesale | Commercial and industrial [Member] | Current and less than 30 days past due and still accruing [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	95,824	93,060
Wholesale | Commercial and industrial [Member] | 30-89 days past due and still accruing [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	460	266
Wholesale | Commercial and industrial [Member] | 90 days or more past due and still accruing [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	24	0
Wholesale | Commercial and industrial [Member] | Nonaccrual [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	781	889
Wholesale | Commercial and industrial [Member] | Total U.S.[Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	65,967	63,402
Wholesale | Commercial and industrial [Member] | Total non-U.S.[Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	31,122	30,813
Wholesale | Real estate [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	56,747	54,684
Percentage of total criticized to total retained loans	7.77%	8.76%
Percentage of nonaccrual loans to total retained loans	1.43%	1.62%
Wholesale | Real estate [Member] | Investment grade [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	35,299	33,920
Wholesale | Real estate [Member] | Total noninvestment grade [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	21,448	20,764
Wholesale | Real estate [Member] | Non Criticized [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	17,040	15,972
Wholesale | Real estate [Member] | Criticized performing [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	3,599	3,906
Wholesale | Real estate [Member] | Criticized total nonaccrual [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	809	886
Wholesale | Real estate [Member] | Current and less than 30 days past due and still accruing [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	55,572	53,387
Wholesale | Real estate [Member] | 30-89 days past due and still accruing [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	321	327
Wholesale | Real estate [Member] | 90 days or more past due and still accruing [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	45	84
Wholesale | Real estate [Member] | Nonaccrual [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	809	886
Wholesale | Real estate [Member] | Total U.S.[Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	54,648	53,187
Wholesale | Real estate [Member] | Total non-U.S.[Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	2,099	1,497
Wholesale | Financial institutions [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	35,629	38,219
Percentage of total criticized to total retained loans	0.74%	0.74%
Percentage of nonaccrual loans to total retained loans	0.06%	0.10%
Wholesale | Financial institutions [Member] | Investment grade [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	26,720	28,804
Wholesale | Financial institutions [Member] | Total noninvestment grade [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	8,909	9,415
Wholesale | Financial institutions [Member] | Non Criticized [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	8,647	9,132
Wholesale | Financial institutions [Member] | Criticized performing [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	239	246
Wholesale | Financial institutions [Member] | Criticized total nonaccrual [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	23	37
Wholesale | Financial institutions [Member] | Current and less than 30 days past due and still accruing [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	35,576	38,129
Wholesale | Financial institutions [Member] | 30-89 days past due and still accruing [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	30	51
Wholesale | Financial institutions [Member] | 90 days or more past due and still accruing [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	0	2
Wholesale | Financial institutions [Member] | Nonaccrual [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	23	37
Wholesale | Financial institutions [Member] | Total U.S.[Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	8,630	8,223
Wholesale | Financial institutions [Member] | Total non-U.S.[Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	26,999	29,996
Wholesale | Government agencies [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	7,814	7,819
Percentage of total criticized to total retained loans	0.24%	0.26%
Percentage of nonaccrual loans to total retained loans	0.18%	0.20%
Wholesale | Government agencies [Member] | Investment grade [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	7,420	7,421
Wholesale | Government agencies [Member] | Total noninvestment grade [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	394	398
Wholesale | Government agencies [Member] | Non Criticized [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	375	378
Wholesale | Government agencies [Member] | Criticized performing [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	5	4
Wholesale | Government agencies [Member] | Criticized total nonaccrual [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	14	16
Wholesale | Government agencies [Member] | Current and less than 30 days past due and still accruing [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	7,750	7,780
Wholesale | Government agencies [Member] | 30-89 days past due and still accruing [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	50	23
Wholesale | Government agencies [Member] | 90 days or more past due and still accruing [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	0	0
Wholesale | Government agencies [Member] | Nonaccrual [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	14	16
Wholesale | Government agencies [Member] | Total U.S.[Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	7,166	7,236
Wholesale | Government agencies [Member] | Total non-U.S.[Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	648	583
Wholesale | Other [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	86,374	83,458
Percentage of total criticized to total retained loans	1.17%	1.65%
Percentage of nonaccrual loans to total retained loans	0.36%	0.68%
Wholesale | Other [Member] | Investment grade [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	76,789	74,497
Wholesale | Other [Member] | Total noninvestment grade [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	9,585	8,961
Wholesale | Other [Member] | Non Criticized [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	8,572	7,583
Wholesale | Other [Member] | Criticized performing [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	699	808
Wholesale | Other [Member] | Criticized total nonaccrual [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	314	570
Wholesale | Other [Member] | Current and less than 30 days past due and still accruing [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	85,164	81,802
Wholesale | Other [Member] | 30-89 days past due and still accruing [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	873	1,072
Wholesale | Other [Member] | 90 days or more past due and still accruing [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	23	14
Wholesale | Other [Member] | Nonaccrual [Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	314	570
Wholesale | Other [Member] | Total U.S.[Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	49,679	51,183
Wholesale | Other [Member] | Total non-U.S.[Member]
Loan credit quality and risk ratings [Line Items]
Retained loans	$ 36,695	$ 32,275