Fair Value (Fair Value, by Balance Sheet Grouping) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held-to-maturity securities	$ 1,170	$ 1,253
Loans held-for-sale, net	549	406
Finance receivables and loans, net	119,001	115,251
Deposit liabilities	141,558	137,036
Long-term debt	17,029	22,006
Short-term borrowings	0	2,136
Carrying value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held-to-maturity securities	1,170	1,253
Loans held-for-sale, net	469	315
Finance receivables and loans, net	118,994	115,243
FHLB/FRB stock	738	725
Deposit liabilities	40,953	55,210
Long-term debt	17,029	22,006
Short-term borrowings		2,136
Estimated fair value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held-to-maturity securities	1,204	1,331
Loans held-for-sale, net	469	315
Finance receivables and loans, net	126,044	122,156
FHLB/FRB stock	738	725
Deposit liabilities	41,164	55,932
Long-term debt	19,529	25,471
Short-term borrowings		2,136
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
Long-term debt	0	0
Short-term borrowings		0
Estimated fair value \| Fair value, inputs, level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held-to-maturity securities	1,204	1,331
Loans held-for-sale, net	0	0
Finance receivables and loans, net	0	0
FHLB/FRB stock	738	725
Deposit liabilities	0	0
Long-term debt	12,637	19,161
Short-term borrowings		0
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	469	315
Finance receivables and loans, net	126,044	122,156
FHLB/FRB stock	0	0
Deposit liabilities	41,164	55,932
Long-term debt	$ 6,892	6,310
Short-term borrowings		$ 2,136

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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