Fair Value (Fair Value, by Balance Sheet Grouping) (Details) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held-to-maturity securities	$ 1,047	$ 1,062
Loans held-for-sale, net	524	654
Finance receivables and loans, net	132,553	132,037
Deposit liabilities	154,013	152,297
Short-term borrowings	1,455	2,399
Long-term debt	20,480	17,762
Carrying value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held-to-maturity securities	1,047	1,062
Loans held-for-sale, net	500	641
Finance receivables and loans, net	132,551	132,034
FHLB/FRB stock	720	719
Deposit liabilities	52,311	42,336
Short-term borrowings	1,455	2,399
Long-term debt	20,480	17,762
Estimated fair value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held-to-maturity securities	891	884
Loans held-for-sale, net	500	641
Finance receivables and loans, net	134,325	133,856
FHLB/FRB stock	720	719
Deposit liabilities	52,251	41,909
Short-term borrowings	1,487	2,417
Long-term debt	20,934	18,252
Estimated fair value \| Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held-to-maturity securities	0	0
Loans held-for-sale, net	0	0
Finance receivables and loans, net	0	0
FHLB/FRB stock	0	0
Deposit liabilities	0	0
Short-term borrowings	0	0
Long-term debt	0	0
Estimated fair value \| Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held-to-maturity securities	891	884
Loans held-for-sale, net	0	0
Finance receivables and loans, net	0	0
FHLB/FRB stock	720	719
Deposit liabilities	0	0
Short-term borrowings	0	0
Long-term debt	14,044	12,989
Estimated fair value \| Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held-to-maturity securities	0	0
Loans held-for-sale, net	500	641
Finance receivables and loans, net	134,325	133,856
FHLB/FRB stock	0	0
Deposit liabilities	52,251	41,909
Short-term borrowings	1,487	2,417
Long-term debt	$ 6,890	$ 5,263

Amount excluding accrued interest, after allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity).

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