Fair Value (Fair Value, by Balance Sheet Grouping) (Details) - USD ($) $ in Millions	Jun. 30, 2022	Dec. 31, 2021
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held-to-maturity securities	$ 1,112	$ 1,170
Loans held-for-sale, net	798	549
Finance receivables and loans, net	125,007	119,001
Deposit liabilities	140,401	141,558
Short-term borrowings	7,775	0
Long-term debt	16,984	17,029
Carrying value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held-to-maturity securities	1,112	1,170
Loans held-for-sale, net	717	469
Finance receivables and loans, net	125,000	118,994
FHLB/FRB stock	997	738
Deposit liabilities	38,629	40,953
Short-term borrowings	7,775
Long-term debt	16,984	17,029
Estimated fair value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held-to-maturity securities	998	1,204
Loans held-for-sale, net	717	469
Finance receivables and loans, net	128,544	126,044
FHLB/FRB stock	997	738
Deposit liabilities	38,312	41,164
Short-term borrowings	7,779
Long-term debt	17,826	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	998	1,204
Loans held-for-sale, net	0	0
Finance receivables and loans, net	0	0
FHLB/FRB stock	997	738
Deposit liabilities	0	0
Short-term borrowings	0
Long-term debt	11,447	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	717	469
Finance receivables and loans, net	128,544	126,044
FHLB/FRB stock	0	0
Deposit liabilities	38,312	41,164
Short-term borrowings	7,779
Long-term debt	$ 6,379	$ 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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