Fair Value Disclosures (Assets and Liabilities Measured at Fair Value on a Recurring Basis) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2014	Sep. 30, 2015
Assets at Fair Value
Netting	$ (639,977)	$ (507,525)
Investments	6,651	5,604
Trading assets, fair value	256,801	237,811
AFS securities	69,216	61,159
Securities received as collateral	21,316	9,456
Securities purchased under agreement to resell	1,113	809
Intangible assets	6	5
Liabilities at Fair Value
Short-term borrowings	1,765	1,768
Netting	(614,094)	(488,089)
Total trading liabilities	107,381	125,525
Obligation to return securities received as collateral	25,685	20,328
Securities sold under agreement to repurchase	612	597
Other secured financings	4,504	3,450
Long-term borrowings	31,774	31,387
AFS securities
Assets at Fair Value
AFS securities	69,216	61,159
Recurring
Assets at Fair Value
U.S. government and agency securities	36,004	38,377
Other sovereign government obligations	23,078	27,101
Corporate and other debt	38,947	34,629
Corporate equities	114,119	97,089
Derivative and other contracts	36,394	33,294
Netting	(639,977)	(507,525)
Investments	6,651	5,604
Physical commodities	1,608	1,717
Trading assets, fair value	256,801	237,811
Securities received as collateral	21,316	9,456
Securities purchased under agreement to resell	1,113	809
Intangible assets	6	5
Total assets measured at fair value	348,452	309,240
Liabilities at Fair Value
Short-term borrowings	1,765	1,768
U.S. government and agency securities	15,558	15,685
Other sovereign government obligations	13,762	15,990
Corporate and other debt	6,138	6,818
Corporate equities	31,711	51,259
Derivative and other contracts	40,212	35,773
Netting	(614,094)	(488,089)
Total trading liabilities	107,381	125,525
Obligation to return securities received as collateral	25,685	20,328
Securities sold under agreement to repurchase	612	597
Other secured financings	4,504	3,450
Long-term borrowings	31,774	31,387
Total liabilities measure at fair value	171,721	183,055
Recurring | Net Asset Value
Assets at Fair Value
Investments	5,009	4,278
Recurring | U.S. Treasury Securities
Assets at Fair Value
U.S. government and agency securities	16,961	18,359
Liabilities at Fair Value
U.S. government and agency securities	14,199	14,524
Recurring | U.S. Agency Securities
Assets at Fair Value
U.S. government and agency securities	19,043	20,018
Liabilities at Fair Value
U.S. government and agency securities	1,359	1,161
Recurring | State and Municipal Securities
Assets at Fair Value
Corporate and other debt	2,049	1,987
Liabilities at Fair Value
Corporate and other debt	1	3
Recurring | Residential Mortgage-backed Securities
Assets at Fair Value
Corporate and other debt	2,166	2,150
Recurring | Commercial Mortgage-backed Securities
Assets at Fair Value
Corporate and other debt	1,580	1,947
Recurring | Asset-backed Securities
Assets at Fair Value
Corporate and other debt	659	802
Recurring | Corporate Bonds
Assets at Fair Value
Corporate and other debt	16,186	13,433
Liabilities at Fair Value
Corporate and other debt	6,021	6,802
Recurring | Collateralized Debt and Loan Obligations
Assets at Fair Value
Corporate and other debt	1,893	732
Recurring | Loans and Lending Commitments
Assets at Fair Value
Corporate and other debt	11,962	11,334
Recurring | Lending Commitments
Liabilities at Fair Value
Corporate and other debt	15	2
Recurring | Other Debt
Assets at Fair Value
Corporate and other debt	2,452	2,244
Liabilities at Fair Value
Corporate and other debt	101	11
Recurring | Interest Rate Contracts
Assets at Fair Value
Derivative and other contracts	498,173	371,523
Liabilities at Fair Value
Derivative and other contracts	472,578	349,657
Recurring | Credit Contracts
Assets at Fair Value
Derivative and other contracts	32,182	24,781
Liabilities at Fair Value
Derivative and other contracts	32,109	24,642
Recurring | Foreign Exchange Contracts
Assets at Fair Value
Derivative and other contracts	73,101	71,250
Liabilities at Fair Value
Derivative and other contracts	72,352	72,934
Recurring | Equity Contracts
Assets at Fair Value
Derivative and other contracts	48,124	51,660
Liabilities at Fair Value
Derivative and other contracts	55,572	57,411
Recurring | Commodity Contracts
Assets at Fair Value
Derivative and other contracts	24,415	21,241
Liabilities at Fair Value
Derivative and other contracts	21,523	19,167
Recurring | Other Contracts
Assets at Fair Value
Derivative and other contracts	376	364
Liabilities at Fair Value
Derivative and other contracts	172	51
Recurring | Principal Investments
Assets at Fair Value
Investments	896	661
Recurring | Other Investments
Assets at Fair Value
Investments	746	665
Recurring | AFS securities
Assets at Fair Value
AFS securities	69,216	61,159
Recurring | Level 1
Assets at Fair Value
U.S. government and agency securities	17,811	19,687
Other sovereign government obligations	15,149	19,597
Corporate and other debt	0	0
Corporate equities	112,490	96,023
Derivative and other contracts	512	578
Netting	(4,910)	(4,652)
Investments	283	172
Physical commodities	0	0
Trading assets, fair value	146,245	136,057
Securities received as collateral	21,265	9,455
Securities purchased under agreement to resell	0	0
Intangible assets	0	0
Total assets measured at fair value	204,710	173,277
Liabilities at Fair Value
Short-term borrowings	0	0
U.S. government and agency securities	15,473	15,550
Other sovereign government obligations	11,653	13,611
Corporate and other debt	0	0
Corporate equities	31,340	50,017
Derivative and other contracts	946	724
Netting	(4,910)	(4,652)
Total trading liabilities	59,412	79,902
Obligation to return securities received as collateral	25,629	20,327
Securities sold under agreement to repurchase	0	0
Other secured financings	0	0
Long-term borrowings	0	0
Total liabilities measure at fair value	85,041	100,229
Recurring | Level 1 | U.S. Treasury Securities
Assets at Fair Value
U.S. government and agency securities	16,961	18,359
Liabilities at Fair Value
U.S. government and agency securities	14,199	14,524
Recurring | Level 1 | U.S. Agency Securities
Assets at Fair Value
U.S. government and agency securities	850	1,328
Liabilities at Fair Value
U.S. government and agency securities	1,274	1,026
Recurring | Level 1 | State and Municipal Securities
Assets at Fair Value
Corporate and other debt	0	0
Liabilities at Fair Value
Corporate and other debt	0	0
Recurring | Level 1 | Residential Mortgage-backed Securities
Assets at Fair Value
Corporate and other debt	0	0
Recurring | Level 1 | Commercial Mortgage-backed Securities
Assets at Fair Value
Corporate and other debt	0	0
Recurring | Level 1 | Asset-backed Securities
Assets at Fair Value
Corporate and other debt	0	0
Recurring | Level 1 | Corporate Bonds
Assets at Fair Value
Corporate and other debt	0	0
Liabilities at Fair Value
Corporate and other debt	0	0
Recurring | Level 1 | Collateralized Debt and Loan Obligations
Assets at Fair Value
Corporate and other debt	0	0
Recurring | Level 1 | Loans and Lending Commitments
Assets at Fair Value
Corporate and other debt	0	0
Recurring | Level 1 | Lending Commitments
Liabilities at Fair Value
Corporate and other debt	0	0
Recurring | Level 1 | Other Debt
Assets at Fair Value
Corporate and other debt	0	0
Liabilities at Fair Value
Corporate and other debt	0	0
Recurring | Level 1 | Interest Rate Contracts
Assets at Fair Value
Derivative and other contracts	663	860
Liabilities at Fair Value
Derivative and other contracts	602	780
Recurring | Level 1 | Credit Contracts
Assets at Fair Value
Derivative and other contracts	0	0
Liabilities at Fair Value
Derivative and other contracts	0	0
Recurring | Level 1 | Foreign Exchange Contracts
Assets at Fair Value
Derivative and other contracts	83	102
Liabilities at Fair Value
Derivative and other contracts	21	60
Recurring | Level 1 | Equity Contracts
Assets at Fair Value
Derivative and other contracts	571	876
Liabilities at Fair Value
Derivative and other contracts	416	691
Recurring | Level 1 | Commodity Contracts
Assets at Fair Value
Derivative and other contracts	4,105	3,392
Liabilities at Fair Value
Derivative and other contracts	4,817	3,845
Recurring | Level 1 | Other Contracts
Assets at Fair Value
Derivative and other contracts	0	0
Liabilities at Fair Value
Derivative and other contracts	0	0
Recurring | Level 1 | Principal Investments
Assets at Fair Value
Investments	58	23
Recurring | Level 1 | Other Investments
Assets at Fair Value
Investments	225	149
Recurring | Level 1 | AFS securities
Assets at Fair Value
AFS securities	37,200	27,765
Recurring | Level 2
Assets at Fair Value
U.S. government and agency securities	18,193	18,690
Other sovereign government obligations	7,888	7,493
Corporate and other debt	30,903	27,617
Corporate equities	1,357	491
Derivative and other contracts	98,866	90,171
Netting	(564,127)	(437,820)
Investments	201	301
Physical commodities	1,608	1,717
Trading assets, fair value	159,016	146,480
Securities received as collateral	51	0
Securities purchased under agreement to resell	1,113	809
Intangible assets	0	0
Total assets measured at fair value	192,196	180,683
Liabilities at Fair Value
Short-term borrowings	1,765	1,699
U.S. government and agency securities	85	135
Other sovereign government obligations	2,109	2,379
Corporate and other debt	6,017	6,795
Corporate equities	326	1,145
Derivative and other contracts	74,583	71,809
Netting	(564,127)	(437,820)
Total trading liabilities	83,120	82,263
Obligation to return securities received as collateral	56	0
Securities sold under agreement to repurchase	459	443
Other secured financings	4,355	3,109
Long-term borrowings	29,840	28,925
Total liabilities measure at fair value	119,595	116,439
Recurring | Level 2 | U.S. Treasury Securities
Assets at Fair Value
U.S. government and agency securities	0	0
Liabilities at Fair Value
U.S. government and agency securities	0	0
Recurring | Level 2 | U.S. Agency Securities
Assets at Fair Value
U.S. government and agency securities	18,193	18,690
Liabilities at Fair Value
U.S. government and agency securities	85	135
Recurring | Level 2 | State and Municipal Securities
Assets at Fair Value
Corporate and other debt	2,049	1,954
Liabilities at Fair Value
Corporate and other debt	1	3
Recurring | Level 2 | Residential Mortgage-backed Securities
Assets at Fair Value
Corporate and other debt	1,991	1,746
Recurring | Level 2 | Commercial Mortgage-backed Securities
Assets at Fair Value
Corporate and other debt	1,484	1,868
Recurring | Level 2 | Asset-backed Securities
Assets at Fair Value
Corporate and other debt	583	771
Recurring | Level 2 | Corporate Bonds
Assets at Fair Value
Corporate and other debt	15,800	13,207
Liabilities at Fair Value
Corporate and other debt	5,943	6,783
Recurring | Level 2 | Collateralized Debt and Loan Obligations
Assets at Fair Value
Corporate and other debt	741	187
Recurring | Level 2 | Loans and Lending Commitments
Assets at Fair Value
Corporate and other debt	6,088	6,170
Recurring | Level 2 | Lending Commitments
Liabilities at Fair Value
Corporate and other debt	10	2
Recurring | Level 2 | Other Debt
Assets at Fair Value
Corporate and other debt	2,167	1,714
Liabilities at Fair Value
Corporate and other debt	63	7
Recurring | Level 2 | Interest Rate Contracts
Assets at Fair Value
Derivative and other contracts	495,026	368,503
Liabilities at Fair Value
Derivative and other contracts	469,319	346,806
Recurring | Level 2 | Credit Contracts
Assets at Fair Value
Derivative and other contracts	30,813	23,844
Liabilities at Fair Value
Derivative and other contracts	29,997	22,900
Recurring | Level 2 | Foreign Exchange Contracts
Assets at Fair Value
Derivative and other contracts	72,769	70,801
Liabilities at Fair Value
Derivative and other contracts	72,233	72,593
Recurring | Level 2 | Equity Contracts
Assets at Fair Value
Derivative and other contracts	45,967	49,833
Liabilities at Fair Value
Derivative and other contracts	51,405	53,728
Recurring | Level 2 | Commodity Contracts
Assets at Fair Value
Derivative and other contracts	18,042	14,646
Liabilities at Fair Value
Derivative and other contracts	15,584	13,551
Recurring | Level 2 | Other Contracts
Assets at Fair Value
Derivative and other contracts	376	364
Liabilities at Fair Value
Derivative and other contracts	172	51
Recurring | Level 2 | Principal Investments
Assets at Fair Value
Investments	3	97
Recurring | Level 2 | Other Investments
Assets at Fair Value
Investments	198	204
Recurring | Level 2 | AFS securities
Assets at Fair Value
AFS securities	32,016	33,394
Recurring | Level 3
Assets at Fair Value
U.S. government and agency securities	0	0
Other sovereign government obligations	41	11
Corporate and other debt	8,044	7,012
Corporate equities	272	575
Derivative and other contracts	3,736	3,617
Netting	(4,220)	(3,981)
Investments	1,158	853
Physical commodities	0	0
Trading assets, fair value	13,251	12,068
Securities received as collateral	0	1
Securities purchased under agreement to resell	0	0
Intangible assets	6	5
Total assets measured at fair value	13,257	12,074
Liabilities at Fair Value
Short-term borrowings	0	69
U.S. government and agency securities	0	0
Other sovereign government obligations	0	0
Corporate and other debt	121	23
Corporate equities	45	97
Derivative and other contracts	5,520	4,876
Netting	(4,220)	(3,981)
Total trading liabilities	5,686	4,996
Obligation to return securities received as collateral	0	1
Securities sold under agreement to repurchase	153	154
Other secured financings	149	341
Long-term borrowings	1,934	2,462
Total liabilities measure at fair value	7,922	8,023
Recurring | Level 3 | U.S. Treasury Securities
Assets at Fair Value
U.S. government and agency securities	0	0
Liabilities at Fair Value
U.S. government and agency securities	0	0
Recurring | Level 3 | U.S. Agency Securities
Assets at Fair Value
U.S. government and agency securities	0	0
Liabilities at Fair Value
U.S. government and agency securities	0	0
Recurring | Level 3 | State and Municipal Securities
Assets at Fair Value
Corporate and other debt	0	33
Liabilities at Fair Value
Corporate and other debt	0	0
Recurring | Level 3 | Residential Mortgage-backed Securities
Assets at Fair Value
Corporate and other debt	175	404
Recurring | Level 3 | Commercial Mortgage-backed Securities
Assets at Fair Value
Corporate and other debt	96	79
Recurring | Level 3 | Asset-backed Securities
Assets at Fair Value
Corporate and other debt	76	31
Recurring | Level 3 | Corporate Bonds
Assets at Fair Value
Corporate and other debt	386	226
Liabilities at Fair Value
Corporate and other debt	78	19
Recurring | Level 3 | Collateralized Debt and Loan Obligations
Assets at Fair Value
Corporate and other debt	1,152	545
Recurring | Level 3 | Loans and Lending Commitments
Assets at Fair Value
Corporate and other debt	5,874	5,164
Recurring | Level 3 | Lending Commitments
Liabilities at Fair Value
Corporate and other debt	5	0
Recurring | Level 3 | Other Debt
Assets at Fair Value
Corporate and other debt	285	530
Liabilities at Fair Value
Corporate and other debt	38	4
Recurring | Level 3 | Interest Rate Contracts
Assets at Fair Value
Derivative and other contracts	2,484	2,160
Liabilities at Fair Value
Derivative and other contracts	2,657	2,071
Recurring | Level 3 | Credit Contracts
Assets at Fair Value
Derivative and other contracts	1,369	937
Liabilities at Fair Value
Derivative and other contracts	2,112	1,742
Recurring | Level 3 | Foreign Exchange Contracts
Assets at Fair Value
Derivative and other contracts	249	347
Liabilities at Fair Value
Derivative and other contracts	98	281
Recurring | Level 3 | Equity Contracts
Assets at Fair Value
Derivative and other contracts	1,586	951
Asset derivative equity contract increased by	57
Liabilities at Fair Value
Derivative and other contracts	3,751	2,992
Liabilities derivative equity contract increased by	842
Recurring | Level 3 | Commodity Contracts
Assets at Fair Value
Derivative and other contracts	2,268	3,203
Liabilities at Fair Value
Derivative and other contracts	1,122	1,771
Recurring | Level 3 | Other Contracts
Assets at Fair Value
Derivative and other contracts	0	0
Liabilities at Fair Value
Derivative and other contracts	0	0
Recurring | Level 3 | Principal Investments
Assets at Fair Value
Investments	835	541
Recurring | Level 3 | Other Investments
Assets at Fair Value
Investments	323	312
Recurring | Level 3 | AFS securities
Assets at Fair Value
AFS securities	0	0
Recurring | Counterparty and Cash Collateral Netting
Assets at Fair Value
Derivative and other contracts	(66,720)	(61,072)
Netting	(66,720)	(61,072)
Trading assets, fair value	(66,720)	(61,072)
Total assets measured at fair value	(66,720)	(61,072)
Liabilities at Fair Value
Derivative and other contracts	(40,837)	(41,636)
Netting	(40,837)	(41,636)
Total trading liabilities	(40,837)	(41,636)
Total liabilities measure at fair value	$ (40,837)	$ (41,636)