Fair Value, Assets and Liabilities Recorded at Fair Value on a Recurring Basis (Details) - USD ($) $ in Millions		Mar. 31, 2019	Dec. 31, 2018
Assets:
Trading debt securities		$ 70,378	$ 69,989
Available-for-sale, at fair value		268,099	269,912
Mortgage servicing rights		13,336	14,649
Derivative assets		34,949	34,560
Net amounts in consolidated balance sheet, assets		11,238	10,770
Marketable equity securities		32,586	29,556
Equity securities	[1]	58,440	55,148
Liabilities:
Total derivative liabilities		(33,417)	(32,047)
Fair value liability derivatives, net		(7,393)	(8,499)
Interest rate contract [Member]
Assets:
Net amounts in consolidated balance sheet, assets		7,095	6,406
Liabilities:
Fair value liability derivatives, net		(2,501)	(3,156)
Commodity contract [Member]
Assets:
Net amounts in consolidated balance sheet, assets		682	739
Liabilities:
Fair value liability derivatives, net		(497)	(1,609)
Equity contract [Member]
Assets:
Net amounts in consolidated balance sheet, assets		2,151	2,227
Liabilities:
Fair value liability derivatives, net		(2,806)	(2,133)
Foreign exchange contract [Member]
Assets:
Net amounts in consolidated balance sheet, assets		1,258	1,359
Liabilities:
Fair value liability derivatives, net		(1,577)	(1,591)
US Treasury and Government [Member]
Assets:
Available-for-sale, at fair value		15,106	13,348
Securities of U.S. states and political subdivisions [Member]
Assets:
Available-for-sale, at fair value		49,700	49,264
Mortgage-backed securities [Member]
Assets:
Available-for-sale, at fair value		156,491	160,203
Federal agencies [Member]
Assets:
Available-for-sale, at fair value		150,663	153,203
Residential [Member]
Assets:
Available-for-sale, at fair value		1,456	2,775
Commercial [Member]
Assets:
Available-for-sale, at fair value		4,372	4,225
Corporate debt securities [Member]
Assets:
Available-for-sale, at fair value		6,354	6,271
Collateralized loan obligations [Member]
Assets:
Available-for-sale, at fair value		35,315	35,343
Collateralized debt obligations [Member]
Assets:
Available-for-sale, at fair value		755	800
Other debt securities [Member]
Assets:
Available-for-sale, at fair value		5,133	5,483
Fair Value, Measurements, Recurring [Member]
Assets:
Mortgage loans held for sale		11,091	11,771
Loans held for sale		998	1,469
Loans		225	244
Mortgage servicing rights		13,336	14,649
Fair value asset derivatives, netting		(23,711)	(23,790)
Net amounts in consolidated balance sheet, assets		11,238	10,770
Total assets recorded at fair value		407,951	408,360
Liabilities:
Fair value liability derivatives, netting		26,024	23,548
Fair value liability derivatives, net		(7,393)	(8,499)
Total short sale liabilities		(21,586)	(19,720)
Other liabilities (2)		(2)	(2)
Total liabilities recorded at fair value		(28,981)	(28,221)
Fair Value, Measurements, Recurring [Member] | Excluding NAV Investments [Member]
Assets:
Total assets recorded at fair value		407,834	408,258
Fair Value, Measurements, Recurring [Member] | Interest rate contract [Member]
Assets:
Derivative assets		20,449	18,435
Liabilities:
Total derivative liabilities		(17,262)	(16,308)
Fair Value, Measurements, Recurring [Member] | Commodity contract [Member]
Assets:
Derivative assets		1,528	1,588
Liabilities:
Total derivative liabilities		(1,160)	(2,336)
Fair Value, Measurements, Recurring [Member] | Equity contract [Member]
Assets:
Derivative assets		6,768	7,545
Liabilities:
Total derivative liabilities		(7,960)	(6,010)
Fair Value, Measurements, Recurring [Member] | Foreign exchange contract [Member]
Assets:
Derivative assets		5,900	6,714
Liabilities:
Total derivative liabilities		(6,712)	(7,113)
Fair Value, Measurements, Recurring [Member] | Credit Risk Contract [Member]
Assets:
Derivative assets		304	278
Liabilities:
Total derivative liabilities		(323)	(280)
Fair Value, Measurements, Recurring [Member] | Debt securities [Member]
Assets:
Trading debt securities		70,378	69,989
Available-for-sale, at fair value		268,099	269,912
Fair Value, Measurements, Recurring [Member] | US Treasury and Government [Member]
Assets:
Trading debt securities		22,555	23,417
Available-for-sale, at fair value		15,106	13,348
Liabilities:
Total short sale liabilities		(12,781)	(12,261)
Fair Value, Measurements, Recurring [Member] | Securities of U.S. states and political subdivisions [Member]
Assets:
Trading debt securities		3,385	3,275
Available-for-sale, at fair value		49,700	49,264
Fair Value, Measurements, Recurring [Member] | Other trading debt securities [Member]
Assets:
Trading debt securities		26	22
Fair Value, Measurements, Recurring [Member] | Mortgage-backed securities [Member]
Assets:
Trading debt securities		31,162	30,715
Available-for-sale, at fair value		156,491	160,203
Fair Value, Measurements, Recurring [Member] | Federal agencies [Member]
Assets:
Available-for-sale, at fair value		150,663	153,203
Fair Value, Measurements, Recurring [Member] | Residential [Member]
Assets:
Available-for-sale, at fair value		1,456	2,775
Fair Value, Measurements, Recurring [Member] | Commercial [Member]
Assets:
Available-for-sale, at fair value		4,372	4,225
Fair Value, Measurements, Recurring [Member] | Mortgage backed securities, other [Member]
Liabilities:
Total short sale liabilities		(404)	(47)
Fair Value, Measurements, Recurring [Member] | Corporate debt securities [Member]
Assets:
Trading debt securities		11,114	10,757
Available-for-sale, at fair value		6,354	6,271
Liabilities:
Total short sale liabilities		(5,075)	(4,505)
Fair Value, Measurements, Recurring [Member] | Collateralized loan obligations [Member]
Assets:
Trading debt securities		949	910
Available-for-sale, at fair value		35,315	35,343
Fair Value, Measurements, Recurring [Member] | Asset-backed securities [Member]
Assets:
Trading debt securities		1,187	893
Available-for-sale, at fair value		5,132	5,482
Fair Value, Measurements, Recurring [Member] | Auto loans and leases [Member]
Assets:
Available-for-sale, at fair value		945	925
Fair Value, Measurements, Recurring [Member] | Home equity loans [Member]
Assets:
Available-for-sale, at fair value		14	112
Fair Value, Measurements, Recurring [Member] | Other asset-backed securities [Member]
Assets:
Available-for-sale, at fair value		4,173	4,445
Fair Value, Measurements, Recurring [Member] | Other debt securities [Member]
Assets:
Available-for-sale, at fair value		1	1
Fair Value, Measurements, Recurring [Member] | Equity securities [Member]
Liabilities:
Total short sale liabilities		(3,326)	(2,904)
Fair Value, Measurements, Recurring [Member] | Equity securities [Member] | Excluding NAV Investments [Member]
Assets:
Equity securities		32,469	29,454
Fair Value, Measurements, Recurring [Member] | Marketable equity securities [Member] | Excluding NAV Investments [Member]
Assets:
Marketable equity securities		26,068	23,962
Fair Value, Measurements, Recurring [Member] | Nonmarketable equity securities [Member] | Excluding NAV Investments [Member]
Assets:
Nonmarketable equity securities		6,401	5,492
Fair Value, Measurements, Recurring [Member] | Other securities sold, not yet purchased [Member]
Liabilities:
Total short sale liabilities		0	(3)
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Assets:
Mortgage loans held for sale		0	0
Loans held for sale		0	0
Loans		0	0
Mortgage servicing rights		0	0
Fair value asset derivatives, netting		0	0
Net amounts in consolidated balance sheet, assets		2,020	1,711
Liabilities:
Fair value liability derivatives, netting		0	0
Fair value liability derivatives, net		(1,421)	(1,525)
Total short sale liabilities		(15,887)	(14,752)
Other liabilities (2)		0	0
Total liabilities recorded at fair value		(17,308)	(16,277)
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Excluding NAV Investments [Member]
Assets:
Total assets recorded at fair value		56,952	55,874
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Interest rate contract [Member]
Assets:
Derivative assets		67	46
Liabilities:
Total derivative liabilities		(18)	(21)
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Commodity contract [Member]
Assets:
Derivative assets		0	0
Liabilities:
Total derivative liabilities		0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Equity contract [Member]
Assets:
Derivative assets		1,936	1,648
Liabilities:
Total derivative liabilities		(1,382)	(1,492)
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Foreign exchange contract [Member]
Assets:
Derivative assets		17	17
Liabilities:
Total derivative liabilities		(21)	(12)
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Credit Risk Contract [Member]
Assets:
Derivative assets		0	0
Liabilities:
Total derivative liabilities		0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Debt securities [Member]
Assets:
Trading debt securities		17,584	20,525
Available-for-sale, at fair value		12,180	10,433
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | US Treasury and Government [Member]
Assets:
Trading debt securities		17,584	20,525
Available-for-sale, at fair value		12,144	10,399
Liabilities:
Total short sale liabilities		(12,562)	(11,850)
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Securities of U.S. states and political subdivisions [Member]
Assets:
Trading debt securities		0	0
Available-for-sale, at fair value		0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Other trading debt securities [Member]
Assets:
Trading debt securities		0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Mortgage-backed securities [Member]
Assets:
Trading debt securities		0	0
Available-for-sale, at fair value		0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Federal agencies [Member]
Assets:
Available-for-sale, at fair value		0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Residential [Member]
Assets:
Available-for-sale, at fair value		0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Commercial [Member]
Assets:
Available-for-sale, at fair value		0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Mortgage backed securities, other [Member]
Liabilities:
Total short sale liabilities		0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Corporate debt securities [Member]
Assets:
Trading debt securities		0	0
Available-for-sale, at fair value		36	34
Liabilities:
Total short sale liabilities		0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Collateralized loan obligations [Member]
Assets:
Trading debt securities		0	0
Available-for-sale, at fair value		0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Asset-backed securities [Member]
Assets:
Trading debt securities		0	0
Available-for-sale, at fair value		0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Auto loans and leases [Member]
Assets:
Available-for-sale, at fair value		0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Home equity loans [Member]
Assets:
Available-for-sale, at fair value		0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Other asset-backed securities [Member]
Assets:
Available-for-sale, at fair value		0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Other debt securities [Member]
Assets:
Available-for-sale, at fair value		0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Equity securities [Member]
Liabilities:
Total short sale liabilities		(3,325)	(2,902)
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Equity securities [Member] | Excluding NAV Investments [Member]
Assets:
Equity securities		25,168	23,205
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Marketable equity securities [Member] | Excluding NAV Investments [Member]
Assets:
Marketable equity securities		25,168	23,205
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Nonmarketable equity securities [Member] | Excluding NAV Investments [Member]
Assets:
Nonmarketable equity securities		0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Other securities sold, not yet purchased [Member]
Liabilities:
Total short sale liabilities		0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Assets:
Mortgage loans held for sale		10,093	10,774
Loans held for sale		927	1,409
Loans		0	0
Mortgage servicing rights		0	0
Fair value asset derivatives, netting		0	0
Net amounts in consolidated balance sheet, assets		31,120	31,279
Liabilities:
Fair value liability derivatives, netting		0	0
Fair value liability derivatives, net		(30,141)	(28,973)
Total short sale liabilities		(5,699)	(4,968)
Other liabilities (2)		0	0
Total liabilities recorded at fair value		(35,840)	(33,941)
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Excluding NAV Investments [Member]
Assets:
Total assets recorded at fair value		349,437	350,852
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Interest rate contract [Member]
Assets:
Derivative assets		20,254	18,294
Liabilities:
Total derivative liabilities		(17,217)	(16,217)
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Commodity contract [Member]
Assets:
Derivative assets		1,503	1,535
Liabilities:
Total derivative liabilities		(1,117)	(2,287)
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Equity contract [Member]
Assets:
Derivative assets		3,275	4,582
Liabilities:
Total derivative liabilities		(4,859)	(3,186)
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Foreign exchange contract [Member]
Assets:
Derivative assets		5,872	6,689
Liabilities:
Total derivative liabilities		(6,664)	(7,067)
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Credit Risk Contract [Member]
Assets:
Derivative assets		216	179
Liabilities:
Total derivative liabilities		(284)	(216)
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Debt securities [Member]
Assets:
Trading debt securities		52,463	49,174
Available-for-sale, at fair value		253,914	257,435
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | US Treasury and Government [Member]
Assets:
Trading debt securities		4,971	2,892
Available-for-sale, at fair value		2,962	2,949
Liabilities:
Total short sale liabilities		(219)	(411)
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Securities of U.S. states and political subdivisions [Member]
Assets:
Trading debt securities		3,385	3,272
Available-for-sale, at fair value		49,230	48,820
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Other trading debt securities [Member]
Assets:
Trading debt securities		11	6
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Mortgage-backed securities [Member]
Assets:
Trading debt securities		31,162	30,715
Available-for-sale, at fair value		156,450	160,162
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Federal agencies [Member]
Assets:
Available-for-sale, at fair value		150,663	153,203
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Residential [Member]
Assets:
Available-for-sale, at fair value		1,456	2,775
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Commercial [Member]
Assets:
Available-for-sale, at fair value		4,331	4,184
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Mortgage backed securities, other [Member]
Liabilities:
Total short sale liabilities		(404)	(47)
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Corporate debt securities [Member]
Assets:
Trading debt securities		11,073	10,723
Available-for-sale, at fair value		5,941	5,867
Liabilities:
Total short sale liabilities		(5,075)	(4,505)
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Collateralized loan obligations [Member]
Assets:
Trading debt securities		674	673
Available-for-sale, at fair value		34,560	34,543
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Asset-backed securities [Member]
Assets:
Trading debt securities		1,187	893
Available-for-sale, at fair value		4,770	5,093
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Auto loans and leases [Member]
Assets:
Available-for-sale, at fair value		945	925
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Home equity loans [Member]
Assets:
Available-for-sale, at fair value		14	112
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Other asset-backed securities [Member]
Assets:
Available-for-sale, at fair value		3,811	4,056
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Other debt securities [Member]
Assets:
Available-for-sale, at fair value		1	1
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Equity securities [Member]
Liabilities:
Total short sale liabilities		(1)	(2)
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Equity securities [Member] | Excluding NAV Investments [Member]
Assets:
Equity securities		920	781
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Marketable equity securities [Member] | Excluding NAV Investments [Member]
Assets:
Marketable equity securities		900	757
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Nonmarketable equity securities [Member] | Excluding NAV Investments [Member]
Assets:
Nonmarketable equity securities		20	24
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Other securities sold, not yet purchased [Member]
Liabilities:
Total short sale liabilities		0	(3)
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Assets:
Mortgage loans held for sale		998	997
Loans held for sale		71	60
Loans		225	244
Mortgage servicing rights		13,336	14,649
Fair value asset derivatives, netting		0	0
Net amounts in consolidated balance sheet, assets		1,809	1,570
Total assets recorded at fair value		25,200	25,300
Liabilities:
Fair value liability derivatives, netting		0	0
Fair value liability derivatives, net		(1,855)	(1,549)
Total short sale liabilities		0	0
Other liabilities (2)		(2)	(2)
Total liabilities recorded at fair value		(1,857)	(1,551)
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Excluding NAV Investments [Member]
Assets:
Total assets recorded at fair value		25,156	25,322
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Interest rate contract [Member]
Assets:
Derivative assets		128	95
Liabilities:
Total derivative liabilities		(27)	(70)
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Commodity contract [Member]
Assets:
Derivative assets		25	53
Liabilities:
Total derivative liabilities		(43)	(49)
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Equity contract [Member]
Assets:
Derivative assets		1,557	1,315
Liabilities:
Total derivative liabilities		(1,719)	(1,332)
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Foreign exchange contract [Member]
Assets:
Derivative assets		11	8
Liabilities:
Total derivative liabilities		(27)	(34)
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Credit Risk Contract [Member]
Assets:
Derivative assets		88	99
Liabilities:
Total derivative liabilities		(39)	(64)
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Debt securities [Member]
Assets:
Trading debt securities		331	290
Available-for-sale, at fair value		2,005	2,044
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | US Treasury and Government [Member]
Assets:
Trading debt securities		0	0
Available-for-sale, at fair value		0	0
Liabilities:
Total short sale liabilities		0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Securities of U.S. states and political subdivisions [Member]
Assets:
Trading debt securities		0	3
Available-for-sale, at fair value		470	444
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Other trading debt securities [Member]
Assets:
Trading debt securities		15	16
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Mortgage-backed securities [Member]
Assets:
Trading debt securities		0	0
Available-for-sale, at fair value		41	41
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Federal agencies [Member]
Assets:
Available-for-sale, at fair value		0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Residential [Member]
Assets:
Available-for-sale, at fair value		0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Commercial [Member]
Assets:
Available-for-sale, at fair value		41	41
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Mortgage backed securities, other [Member]
Liabilities:
Total short sale liabilities		0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Corporate debt securities [Member]
Assets:
Trading debt securities		41	34
Available-for-sale, at fair value		377	370
Liabilities:
Total short sale liabilities		0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Collateralized loan obligations [Member]
Assets:
Trading debt securities		275	237
Available-for-sale, at fair value		755	800
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Collateralized debt obligations [Member]
Assets:
Available-for-sale, at fair value		755	800
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Asset-backed securities [Member]
Assets:
Trading debt securities		0	0
Available-for-sale, at fair value		362	389
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Auto loans and leases [Member]
Assets:
Available-for-sale, at fair value		0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Home equity loans [Member]
Assets:
Available-for-sale, at fair value		0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Other asset-backed securities [Member]
Assets:
Available-for-sale, at fair value		362	389
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Other debt securities [Member]
Assets:
Available-for-sale, at fair value		0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Equity securities [Member]
Liabilities:
Total short sale liabilities		0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Equity securities [Member] | Excluding NAV Investments [Member]
Assets:
Equity securities		6,381	5,468
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Marketable equity securities [Member] | Excluding NAV Investments [Member]
Assets:
Marketable equity securities		0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Nonmarketable equity securities [Member] | Excluding NAV Investments [Member]
Assets:
Nonmarketable equity securities		6,381	5,468
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Other securities sold, not yet purchased [Member]
Liabilities:
Total short sale liabilities		0	0
Fair Value, Measurements, Recurring [Member] | Fair value measured at net asset value per share [Member] | Nonmarketable equity securities [Member] | Including NAV Investments [Member]
Assets:
Nonmarketable equity securities		$ 117	$ 102

[1] (1)Parenthetical amounts represent assets and liabilities that we are required to carry at fair value or have elected the fair value option.