Fair Value (Fair Value, by Balance Sheet Grouping) (Details) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held-to-maturity securities	$ 1,159	$ 1,170
Loans held-for-sale, net	471	549
Finance receivables and loans, net	122,064	119,001
Deposit liabilities	142,475	141,558
Short-term borrowings	3,950	0
Long-term debt	15,885	17,029
Carrying value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held-to-maturity securities	1,159	1,170
Loans held-for-sale, net	376	469
Finance receivables and loans, net	122,057	118,994
FHLB/FRB stock	856	738
Deposit liabilities	37,889	40,953
Short-term borrowings	3,950
Long-term debt	15,885	17,029
Estimated fair value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held-to-maturity securities	1,106	1,204
Loans held-for-sale, net	376	469
Finance receivables and loans, net	126,765	126,044
FHLB/FRB stock	856	738
Deposit liabilities	37,793	41,164
Short-term borrowings	3,950
Long-term debt	17,505	19,529
Estimated fair value \| Fair value, inputs, 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
Long-term debt	0	0
Estimated fair value \| Fair value, inputs, level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held-to-maturity securities	1,106	1,204
Loans held-for-sale, net	0	0
Finance receivables and loans, net	0	0
FHLB/FRB stock	856	738
Deposit liabilities	0	0
Short-term borrowings	0
Long-term debt	10,991	12,637
Estimated fair value \| Fair value, inputs, level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held-to-maturity securities	0	0
Loans held-for-sale, net	376	469
Finance receivables and loans, net	126,765	126,044
FHLB/FRB stock	0	0
Deposit liabilities	37,793	41,164
Short-term borrowings	3,950
Long-term debt	$ 6,514	$ 6,892

The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others.

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

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