Finance Receivables and Loans, Net (Financing Receivable Credit Quality Indicators Commercial) (Details) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Financing Receivable, Credit Quality Indicator [Line Items]
Total finance receivables and loans	$ 135,748	$ 122,268
Commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, originated, current fiscal year	2,915	2,419
Year two, originated, fiscal year before current fiscal year	2,035	1,896
Year three, originated, two years before current fiscal year	1,871	1,586
Year four, originated, three years before current fiscal year	1,406	783
Year five, originated, four years before current fiscal year	508	663
Originated, more than five years before current fiscal year	1,196	1,052
Revolving loans	19,057	15,512
Revolving loans converted to term	150	131
Total finance receivables and loans	29,138	24,042
Consumer
Financing Receivable, Credit Quality Indicator [Line Items]
Total finance receivables and loans	106,610	98,226
Automotive | Commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, originated, current fiscal year	663	354
Year two, originated, fiscal year before current fiscal year	258	192
Year three, originated, two years before current fiscal year	132	119
Year four, originated, three years before current fiscal year	79	65
Year five, originated, four years before current fiscal year	38	54
Originated, more than five years before current fiscal year	55	74
Revolving loans	13,370	11,371
Revolving loans converted to term	0	0
Total finance receivables and loans	14,595	12,229
Automotive | Consumer
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, originated, current fiscal year		35,802
Year two, originated, fiscal year before current fiscal year		17,736
Year three, originated, two years before current fiscal year		12,010
Year four, originated, three years before current fiscal year		7,028
Year five, originated, four years before current fiscal year		3,610
Originated, more than five years before current fiscal year		2,066
Revolving loans		0
Revolving loans converted to term		0
Total finance receivables and loans	83,286	78,252
Automotive | Pass | Commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, originated, current fiscal year	640	347
Year two, originated, fiscal year before current fiscal year	211	190
Year three, originated, two years before current fiscal year	132	112
Year four, originated, three years before current fiscal year	78	49
Year five, originated, four years before current fiscal year	28	23
Originated, more than five years before current fiscal year	34	56
Revolving loans	12,327	10,741
Revolving loans converted to term	0	0
Total finance receivables and loans	13,450	11,518
Automotive | Special Mention | Commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, originated, current fiscal year	23	7
Year two, originated, fiscal year before current fiscal year	47	1
Year three, originated, two years before current fiscal year	0	7
Year four, originated, three years before current fiscal year	0	15
Year five, originated, four years before current fiscal year	10	31
Originated, more than five years before current fiscal year	21	18
Revolving loans	1,016	589
Revolving loans converted to term	0	0
Total finance receivables and loans	1,117	668
Automotive | Substandard | Commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, originated, current fiscal year	0	0
Year two, originated, fiscal year before current fiscal year	0	1
Year three, originated, two years before current fiscal year	0	0
Year four, originated, three years before current fiscal year	1	1
Year five, originated, four years before current fiscal year	0	0
Originated, more than five years before current fiscal year	0	0
Revolving loans	27	41
Revolving loans converted to term	0	0
Total finance receivables and loans	28	43
Other | Commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, originated, current fiscal year	771	754
Year two, originated, fiscal year before current fiscal year	627	639
Year three, originated, two years before current fiscal year	786	565
Year four, originated, three years before current fiscal year	629	107
Year five, originated, four years before current fiscal year	101	249
Originated, more than five years before current fiscal year	425	299
Revolving loans	5,678	4,138
Revolving loans converted to term	137	123
Total finance receivables and loans	9,154	6,874
Other | Consumer
Financing Receivable, Credit Quality Indicator [Line Items]
Total finance receivables and loans	3,589	1,962
Fair value, option, carrying amount, financing receivable	3	7
Other | Pass | Commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, originated, current fiscal year	594	739
Year two, originated, fiscal year before current fiscal year	469	448
Year three, originated, two years before current fiscal year	607	374
Year four, originated, three years before current fiscal year	419	86
Year five, originated, four years before current fiscal year	54	99
Originated, more than five years before current fiscal year	133	68
Revolving loans	5,344	4,032
Revolving loans converted to term	89	83
Total finance receivables and loans	7,709	5,929
Other | Special Mention | Commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, originated, current fiscal year	177	15
Year two, originated, fiscal year before current fiscal year	158	169
Year three, originated, two years before current fiscal year	175	96
Year four, originated, three years before current fiscal year	95	21
Year five, originated, four years before current fiscal year	47	10
Originated, more than five years before current fiscal year	128	122
Revolving loans	278	93
Revolving loans converted to term	35	17
Total finance receivables and loans	1,093	543
Other | Substandard | Commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, originated, current fiscal year	0	0
Year two, originated, fiscal year before current fiscal year	0	22
Year three, originated, two years before current fiscal year	4	95
Year four, originated, three years before current fiscal year	51	0
Year five, originated, four years before current fiscal year	0	140
Originated, more than five years before current fiscal year	139	83
Revolving loans	55	13
Revolving loans converted to term	13	23
Total finance receivables and loans	262	376
Other | Doubtful | Commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, originated, current fiscal year	0	0
Year two, originated, fiscal year before current fiscal year	0	0
Year three, originated, two years before current fiscal year	0	0
Year four, originated, three years before current fiscal year	64	0
Year five, originated, four years before current fiscal year	0	0
Originated, more than five years before current fiscal year	25	26
Revolving loans	0	0
Revolving loans converted to term	0	0
Total finance receivables and loans	89	26
Other | Loss | Commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, originated, current fiscal year	0
Year two, originated, fiscal year before current fiscal year	0
Year three, originated, two years before current fiscal year	0
Year four, originated, three years before current fiscal year	0
Year five, originated, four years before current fiscal year	0
Originated, more than five years before current fiscal year	0
Revolving loans	1
Revolving loans converted to term	0
Total finance receivables and loans	1
Commercial real estate | Commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, originated, current fiscal year	1,481	1,311
Year two, originated, fiscal year before current fiscal year	1,150	1,065
Year three, originated, two years before current fiscal year	953	902
Year four, originated, three years before current fiscal year	698	611
Year five, originated, four years before current fiscal year	369	360
Originated, more than five years before current fiscal year	716	679
Revolving loans	9	3
Revolving loans converted to term	13	8
Total finance receivables and loans	5,389	4,939
Commercial real estate | Consumer
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, originated, current fiscal year	2,309	10,227
Year two, originated, fiscal year before current fiscal year	10,927	2,215
Year three, originated, two years before current fiscal year	1,950	986
Year four, originated, three years before current fiscal year	821	767
Year five, originated, four years before current fiscal year	590	1,050
Originated, more than five years before current fiscal year	2,922	2,496
Revolving loans	195	244
Revolving loans converted to term	21	27
Total finance receivables and loans	19,735	18,012
Commercial real estate | Pass | Commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, originated, current fiscal year	1,481	1,298
Year two, originated, fiscal year before current fiscal year	1,118	1,060
Year three, originated, two years before current fiscal year	951	873
Year four, originated, three years before current fiscal year	679	604
Year five, originated, four years before current fiscal year	369	342
Originated, more than five years before current fiscal year	716	653
Revolving loans	9	3
Revolving loans converted to term	13	8
Total finance receivables and loans	5,336	4,841
Commercial real estate | Special Mention | Commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, originated, current fiscal year	0	13
Year two, originated, fiscal year before current fiscal year	32	5
Year three, originated, two years before current fiscal year	2	29
Year four, originated, three years before current fiscal year	19	7
Year five, originated, four years before current fiscal year	0	18
Originated, more than five years before current fiscal year	0	19
Revolving loans	0	0
Revolving loans converted to term	0	0
Total finance receivables and loans	$ 53	91
Commercial real estate | Substandard | Commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, originated, current fiscal year		0
Year two, originated, fiscal year before current fiscal year		0
Year three, originated, two years before current fiscal year		0
Year four, originated, three years before current fiscal year		0
Year five, originated, four years before current fiscal year		0
Originated, more than five years before current fiscal year		7
Revolving loans		0
Revolving loans converted to term		0
Total finance receivables and loans		$ 7