Loans and Related Allowance for Credit Losses, Loans by Loan to Value Ratio, Consumer (Details) - USD ($) $ in Millions		Sep. 30, 2020	Dec. 31, 2019
Accounts, Notes, Loans and Financing Receivable [Line Items]
High value properties, threshold		$ 1
By LTV/CLTV:
Total	[1]	920,082	$ 962,265
Purchase credit deteriorated [Member]
By LTV/CLTV:
Total			568
Total Consumer [Member]
By LTV/CLTV:
Term loans by origination year, 2020		60,302
Term loans by origination year, 2019		69,402
Term loans by origination year, 2018		28,153
Term loans by origination year, 2017		35,709
Term loans by origination year, 2016		42,093
Term loans by origination year, Prior		114,037
Revolving loans		78,832
Revolving loans converted to term loans		9,265
Total		437,793	446,546
Total Consumer [Member] | Not purchased credit deteriorated [Member]
By LTV/CLTV:
Total			445,978
Total Consumer [Member] | Not purchased credit deteriorated [Member] | Government insured or guaranteed [Member]
By LTV/CLTV:
Total			11,170
Total Consumer [Member] | Purchase credit deteriorated [Member]
By LTV/CLTV:
Total			568
Total Consumer [Member] | Purchase credit deteriorated [Member] | Non-government insured/guaranteed [Member]
By LTV/CLTV:
Total			$ 568
Total Consumer [Member] | Purchase credit deteriorated [Member] | Non-government insured/guaranteed [Member] | LTV greater than 80% [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, percent of debt-to-value ratio			9.00%
Residential mortgage [Member]
By LTV/CLTV:
Term loans by origination year, 2020		42,656
Term loans by origination year, 2019		49,944
Term loans by origination year, 2018		18,968
Term loans by origination year, 2017		30,244
Term loans by origination year, 2016		37,516
Term loans by origination year, Prior		107,656
Revolving loans		24,390
Revolving loans converted to term loans		8,778
Total		320,152	$ 323,356
Residential mortgage [Member] | Not purchased credit deteriorated [Member]
By LTV/CLTV:
Total			322,788
Residential mortgage [Member] | Not purchased credit deteriorated [Member] | Non-government insured/guaranteed [Member] | LTV 0-60% [Member]
By LTV/CLTV:
Total			166,081
Residential mortgage [Member] | Not purchased credit deteriorated [Member] | Non-government insured/guaranteed [Member] | LTV 60.01-80% [Member]
By LTV/CLTV:
Total			124,458
Residential mortgage [Member] | Not purchased credit deteriorated [Member] | Non-government insured/guaranteed [Member] | LTV 80.01-100% [Member]
By LTV/CLTV:
Total			17,441
Residential mortgage [Member] | Not purchased credit deteriorated [Member] | Non-government insured/guaranteed [Member] | LTV 100.01-120% [Member]
By LTV/CLTV:
Total			1,838
Residential mortgage [Member] | Not purchased credit deteriorated [Member] | Non-government insured/guaranteed [Member] | LTV greater than 120% [Member]
By LTV/CLTV:
Total			674
Residential mortgage [Member] | Not purchased credit deteriorated [Member] | Non-government insured/guaranteed [Member] | No LTV/CLTV available [Member]
By LTV/CLTV:
Total			1,126
Residential mortgage [Member] | Not purchased credit deteriorated [Member] | Government insured or guaranteed [Member]
By LTV/CLTV:
Total			11,170
Residential mortgage [Member] | Purchase credit deteriorated [Member] | Non-government insured/guaranteed [Member]
By LTV/CLTV:
Total			568
Real estate 1-4 family first mortgage [Member]
By LTV/CLTV:
Term loans by origination year, 2020		42,639
Term loans by origination year, 2019		49,903
Term loans by origination year, 2018		18,921
Term loans by origination year, 2017		30,201
Term loans by origination year, 2016		37,480
Term loans by origination year, Prior		106,335
Revolving loans		7,370
Revolving loans converted to term loans		2,141
Total		294,990	293,847
Real estate 1-4 family first mortgage [Member] | Non-government insured/guaranteed [Member] | LTV 0-60% [Member]
By LTV/CLTV:
Term loans by origination year, 2020		12,777
Term loans by origination year, 2019		15,718
Term loans by origination year, 2018		6,606
Term loans by origination year, 2017		13,753
Term loans by origination year, 2016		21,870
Term loans by origination year, Prior		65,355
Revolving loans		5,138
Revolving loans converted to term loans		1,605
Total		142,822
Real estate 1-4 family first mortgage [Member] | Non-government insured/guaranteed [Member] | LTV 60.01-80% [Member]
By LTV/CLTV:
Term loans by origination year, 2020		27,558
Term loans by origination year, 2019		28,843
Term loans by origination year, 2018		9,775
Term loans by origination year, 2017		14,099
Term loans by origination year, 2016		12,226
Term loans by origination year, Prior		12,003
Revolving loans		1,485
Revolving loans converted to term loans		359
Total		106,348
Real estate 1-4 family first mortgage [Member] | Non-government insured/guaranteed [Member] | LTV 80.01-100% [Member]
By LTV/CLTV:
Term loans by origination year, 2020		1,981
Term loans by origination year, 2019		4,293
Term loans by origination year, 2018		1,419
Term loans by origination year, 2017		943
Term loans by origination year, 2016		567
Term loans by origination year, Prior		1,321
Revolving loans		488
Revolving loans converted to term loans		119
Total		11,131
Real estate 1-4 family first mortgage [Member] | Non-government insured/guaranteed [Member] | LTV 100.01-120% [Member]
By LTV/CLTV:
Term loans by origination year, 2020		20
Term loans by origination year, 2019		110
Term loans by origination year, 2018		64
Term loans by origination year, 2017		59
Term loans by origination year, 2016		56
Term loans by origination year, Prior		226
Revolving loans		150
Revolving loans converted to term loans		32
Total		717
Real estate 1-4 family first mortgage [Member] | Non-government insured/guaranteed [Member] | LTV greater than 120% [Member]
By LTV/CLTV:
Term loans by origination year, 2020		10
Term loans by origination year, 2019		49
Term loans by origination year, 2018		22
Term loans by origination year, 2017		21
Term loans by origination year, 2016		23
Term loans by origination year, Prior		100
Revolving loans		53
Revolving loans converted to term loans		12
Total		290
Real estate 1-4 family first mortgage [Member] | Non-government insured/guaranteed [Member] | No LTV/CLTV available [Member]
By LTV/CLTV:
Term loans by origination year, 2020		89
Term loans by origination year, 2019		96
Term loans by origination year, 2018		66
Term loans by origination year, 2017		78
Term loans by origination year, 2016		92
Term loans by origination year, Prior		254
Revolving loans		56
Revolving loans converted to term loans		14
Total		745
Real estate 1-4 family first mortgage [Member] | Government insured or guaranteed [Member]
By LTV/CLTV:
Term loans by origination year, 2020		204
Term loans by origination year, 2019		794
Term loans by origination year, 2018		969
Term loans by origination year, 2017		1,248
Term loans by origination year, 2016		2,646
Term loans by origination year, Prior		27,076
Revolving loans		0
Revolving loans converted to term loans		0
Total		32,937
Real estate 1-4 family first mortgage [Member] | Not purchased credit deteriorated [Member]
By LTV/CLTV:
Total			293,292
Real estate 1-4 family first mortgage [Member] | Not purchased credit deteriorated [Member] | Non-government insured/guaranteed [Member] | LTV 0-60% [Member]
By LTV/CLTV:
Total			151,478
Real estate 1-4 family first mortgage [Member] | Not purchased credit deteriorated [Member] | Non-government insured/guaranteed [Member] | LTV 60.01-80% [Member]
By LTV/CLTV:
Total			114,795
Real estate 1-4 family first mortgage [Member] | Not purchased credit deteriorated [Member] | Non-government insured/guaranteed [Member] | LTV 80.01-100% [Member]
By LTV/CLTV:
Total			13,867
Real estate 1-4 family first mortgage [Member] | Not purchased credit deteriorated [Member] | Non-government insured/guaranteed [Member] | LTV 100.01-120% [Member]
By LTV/CLTV:
Total			860
Real estate 1-4 family first mortgage [Member] | Not purchased credit deteriorated [Member] | Non-government insured/guaranteed [Member] | LTV greater than 120% [Member]
By LTV/CLTV:
Total			338
Real estate 1-4 family first mortgage [Member] | Not purchased credit deteriorated [Member] | Non-government insured/guaranteed [Member] | No LTV/CLTV available [Member]
By LTV/CLTV:
Total			784
Real estate 1-4 family first mortgage [Member] | Not purchased credit deteriorated [Member] | Government insured or guaranteed [Member]
By LTV/CLTV:
Total			11,170
Real estate 1-4 family first mortgage [Member] | Purchase credit deteriorated [Member] | Non-government insured/guaranteed [Member]
By LTV/CLTV:
Total			555
Real estate 1-4 family junior lien mortgage [Member]
By LTV/CLTV:
Term loans by origination year, 2020		17
Term loans by origination year, 2019		41
Term loans by origination year, 2018		47
Term loans by origination year, 2017		43
Term loans by origination year, 2016		36
Term loans by origination year, Prior		1,321
Revolving loans		17,020
Revolving loans converted to term loans		6,637
Total		25,162	29,509
Real estate 1-4 family junior lien mortgage [Member] | Non-government insured/guaranteed [Member] | LTV 0-60% [Member]
By LTV/CLTV:
Term loans by origination year, 2020		0
Term loans by origination year, 2019		0
Term loans by origination year, 2018		0
Term loans by origination year, 2017		0
Term loans by origination year, 2016		0
Term loans by origination year, Prior		572
Revolving loans		8,819
Revolving loans converted to term loans		3,829
Total		13,220
Real estate 1-4 family junior lien mortgage [Member] | Non-government insured/guaranteed [Member] | LTV 60.01-80% [Member]
By LTV/CLTV:
Term loans by origination year, 2020		0
Term loans by origination year, 2019		0
Term loans by origination year, 2018		0
Term loans by origination year, 2017		0
Term loans by origination year, 2016		0
Term loans by origination year, Prior		373
Revolving loans		5,784
Revolving loans converted to term loans		1,740
Total		7,897
Real estate 1-4 family junior lien mortgage [Member] | Non-government insured/guaranteed [Member] | LTV 80.01-100% [Member]
By LTV/CLTV:
Term loans by origination year, 2020		0
Term loans by origination year, 2019		0
Term loans by origination year, 2018		0
Term loans by origination year, 2017		0
Term loans by origination year, 2016		0
Term loans by origination year, Prior		229
Revolving loans		1,772
Revolving loans converted to term loans		773
Total		2,774
Real estate 1-4 family junior lien mortgage [Member] | Non-government insured/guaranteed [Member] | LTV 100.01-120% [Member]
By LTV/CLTV:
Term loans by origination year, 2020		0
Term loans by origination year, 2019		0
Term loans by origination year, 2018		0
Term loans by origination year, 2017		0
Term loans by origination year, 2016		0
Term loans by origination year, Prior		74
Revolving loans		452
Revolving loans converted to term loans		193
Total		719
Real estate 1-4 family junior lien mortgage [Member] | Non-government insured/guaranteed [Member] | LTV greater than 120% [Member]
By LTV/CLTV:
Term loans by origination year, 2020		0
Term loans by origination year, 2019		0
Term loans by origination year, 2018		0
Term loans by origination year, 2017		0
Term loans by origination year, 2016		0
Term loans by origination year, Prior		22
Revolving loans		167
Revolving loans converted to term loans		61
Total		250
Real estate 1-4 family junior lien mortgage [Member] | Non-government insured/guaranteed [Member] | No LTV/CLTV available [Member]
By LTV/CLTV:
Term loans by origination year, 2020		17
Term loans by origination year, 2019		41
Term loans by origination year, 2018		47
Term loans by origination year, 2017		43
Term loans by origination year, 2016		36
Term loans by origination year, Prior		51
Revolving loans		26
Revolving loans converted to term loans		41
Total		$ 302
Real estate 1-4 family junior lien mortgage [Member] | Not purchased credit deteriorated [Member]
By LTV/CLTV:
Total			29,496
Real estate 1-4 family junior lien mortgage [Member] | Not purchased credit deteriorated [Member] | Non-government insured/guaranteed [Member] | LTV 0-60% [Member]
By LTV/CLTV:
Total			14,603
Real estate 1-4 family junior lien mortgage [Member] | Not purchased credit deteriorated [Member] | Non-government insured/guaranteed [Member] | LTV 60.01-80% [Member]
By LTV/CLTV:
Total			9,663
Real estate 1-4 family junior lien mortgage [Member] | Not purchased credit deteriorated [Member] | Non-government insured/guaranteed [Member] | LTV 80.01-100% [Member]
By LTV/CLTV:
Total			3,574
Real estate 1-4 family junior lien mortgage [Member] | Not purchased credit deteriorated [Member] | Non-government insured/guaranteed [Member] | LTV 100.01-120% [Member]
By LTV/CLTV:
Total			978
Real estate 1-4 family junior lien mortgage [Member] | Not purchased credit deteriorated [Member] | Non-government insured/guaranteed [Member] | LTV greater than 120% [Member]
By LTV/CLTV:
Total			336
Real estate 1-4 family junior lien mortgage [Member] | Not purchased credit deteriorated [Member] | Non-government insured/guaranteed [Member] | No LTV/CLTV available [Member]
By LTV/CLTV:
Total			342
Real estate 1-4 family junior lien mortgage [Member] | Not purchased credit deteriorated [Member] | Government insured or guaranteed [Member]
By LTV/CLTV:
Total			0
Real estate 1-4 family junior lien mortgage [Member] | Purchase credit deteriorated [Member] | Non-government insured/guaranteed [Member]
By LTV/CLTV:
Total			$ 13

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