Loans and Related Allowance for Credit Losses (Home Equity and Residential Real Estate Credit Quality Indicators) (Details) - USD ($) $ in Millions		6 Months Ended
		Jun. 30, 2023	Dec. 31, 2022
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Total loans, net	[1]	$ 321,761	$ 326,025
Residential real estate
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Year one		3,073	10,594
Year two		10,328	16,650
Year three		15,944	7,392
Year four		7,073	2,482
Year five		2,360	878
Prior		8,056	7,893
Total loans, net		46,834	45,889
Gross charge-offs
Year two		1
Year four		1
Prior		3
Total		5
Home equity
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Year two			180
Year three		172	2,143
Year four		2,031	997
Year five		929	291
Prior		2,867	2,897
Revolving Loans		8,577	8,902
Revolving Loans Converted to Term		11,624	10,573
Total loans, net		26,200	25,983
Gross charge-offs
Prior		2
Revolving Loans
Revolving Loans Converted to Term		9
Total		11
Greater than or equal to 780 | Residential real estate
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Year one		1,570	6,825
Year two		7,692	12,596
Year three		12,519	5,276
Year four		5,207	1,623
Year five		1,565	463
Prior		4,253	4,027
Total loans, net		32,806	30,810
Greater than or equal to 780 | Home equity
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Year two			110
Year three		110	1,357
Year four		1,319	554
Year five		522	155
Prior		1,770	1,791
Revolving Loans		4,854	5,093
Revolving Loans Converted to Term		6,020	5,545
Total loans, net		14,595	14,605
720 to 779 | Residential real estate
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Year one		1,090	3,172
Year two		2,033	3,024
Year three		2,508	1,369
Year four		1,172	476
Year five		446	180
Prior		1,500	1,457
Total loans, net		8,749	9,678
720 to 779 | Home equity
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Year two			47
Year three		39	515
Year four		467	248
Year five		230	64
Prior		554	567
Revolving Loans		2,230	2,305
Revolving Loans Converted to Term		3,109	2,843
Total loans, net		6,629	6,589
660 to 719 | Residential real estate
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Year one		201	514
Year two		511	744
Year three		691	378
Year four		338	189
Year five		162	98
Prior		786	796
Total loans, net		2,689	2,719
660 to 719 | Home equity
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Year two			19
Year three		18	211
Year four		188	140
Year five		123	42
Prior		295	288
Revolving Loans		1,168	1,146
Revolving Loans Converted to Term		1,656	1,449
Total loans, net		3,448	3,295
Less than 660 | Residential real estate
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Year one		81	63
Year two		63	108
Year three		114	110
Year four		110	88
Year five		90	71
Prior		710	740
Total loans, net		1,168	1,180
Less than 660 | Home equity
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Year two			4
Year three		5	57
Year four		55	54
Year five		53	29
Prior		239	242
Revolving Loans		313	342
Revolving Loans Converted to Term		780	671
Total loans, net		1,445	1,399
No FICO score available | Residential real estate
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Year one		127	11
Year two		13	163
Year three		95	193
Year four		177	67
Year five		59	38
Prior		288	337
Total loans, net		759	809
No FICO score available | Home equity
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Year three			3
Year four		2	1
Year five		1	1
Prior		9	9
Revolving Loans		12	16
Revolving Loans Converted to Term		59	65
Total loans, net		83	95
Government insured or guaranteed loans | Residential real estate
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Year one		4	9
Year two		16	15
Year three		17	66
Year four		69	39
Year five		38	28
Prior		519	536
Total loans, net		663	693
Greater than 100% | Residential real estate
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Year one		22	4
Year two		129	52
Year three		122	20
Year four		40	10
Year five		11	4
Prior		38	41
Total loans, net		362	131
Greater than 100% | Home equity
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Year two			4
Year three		3	14
Year four		15	9
Year five		8	2
Prior		16	15
Revolving Loans		325	268
Revolving Loans Converted to Term		292	137
Total loans, net		659	449
Greater than or equal to 80% to 100% | Residential real estate
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Year one		1,191	1,185
Year two		4,612	678
Year three		1,441	232
Year four		249	84
Year five		79	24
Prior		127	92
Total loans, net		7,699	2,295
Greater than or equal to 80% to 100% | Home equity
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Year two			4
Year three		6	51
Year four		53	27
Year five		26	4
Prior		32	31
Revolving Loans		1,315	854
Revolving Loans Converted to Term		2,074	1,149
Total loans, net		3,506	2,120
Less than 80% | Residential real estate
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Year one		1,804	9,396
Year two		5,571	15,844
Year three		14,351	7,074
Year four		6,715	2,346
Year five		2,232	822
Prior		7,367	7,220
Total loans, net		38,040	42,702
Less than 80% | Home equity
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Year two			172
Year three		163	2,078
Year four		1,963	961
Year five		895	285
Prior		2,819	2,851
Revolving Loans		6,937	7,780
Revolving Loans Converted to Term		9,258	9,287
Total loans, net		22,035	23,414
No LTV available | Residential real estate
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Year one		52
Year two			61
Year three		13
Year four			3
Prior		5	4
Total loans, net		$ 70	$ 68

[1] Our consolidated assets included the following for which we have elected the fair value option: Loans held for sale of $0.8 billion, Loans held for investment of $1.3 billion and Other assets of $0.1 billion at June 30, 2023. Comparable amounts at December 31, 2022 were $0.9 billion, $1.3 billion and $0.1 billion, respectively.