Fair Value (Fair Value, by Balance Sheet Grouping) (Details) - USD ($) $ in Millions	Sep. 30, 2022	Dec. 31, 2021
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held-to-maturity securities	$ 1,084	$ 1,170
Loans held-for-sale, net	808	549
Finance receivables and loans, net	128,845	119,001
Deposit liabilities	145,751	141,558
Short-term borrowings	7,200	0
Long-term debt	16,628	17,029
Carrying value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held-to-maturity securities	1,084	1,170
Loans held-for-sale, net	764	469
Finance receivables and loans, net	128,839	118,994
FHLB/FRB stock	1,010	738
Deposit liabilities	38,507	40,953
Short-term borrowings	7,200
Long-term debt	16,628	17,029
Estimated fair value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held-to-maturity securities	903	1,204
Loans held-for-sale, net	764	469
Finance receivables and loans, net	130,628	126,044
FHLB/FRB stock	1,010	738
Deposit liabilities	37,950	41,164
Short-term borrowings	7,208
Long-term debt	17,084	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	903	1,204
Loans held-for-sale, net	0	0
Finance receivables and loans, net	0	0
FHLB/FRB stock	1,010	738
Deposit liabilities	0	0
Short-term borrowings	0
Long-term debt	10,933	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	764	469
Finance receivables and loans, net	130,628	126,044
FHLB/FRB stock	0	0
Deposit liabilities	37,950	41,164
Short-term borrowings	7,208
Long-term debt	$ 6,151	$ 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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