Fair Value (Fair Value of Financial Instruments) (Details) - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held-to-maturity securities	$ 1,390	$ 1,568
Loans held-for-sale, net	404	158
Finance receivables and loans, net	114,880	126,968
Deposit liabilities	131,036	120,752
Short-term borrowings	3,689	5,531
Long-term debt	29,176	34,027
Reported value measurement
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held-to-maturity securities	1,390	1,568
Loans held-for-sale, net	313	128
Finance receivables and loans, net	114,872	126,957
Federal Home Loan Bank Stock and Federal Reserve Bank Stock	1,000	1,150
Deposit liabilities	60,340	60,146
Short-term borrowings	3,689	5,531
Long-term debt	29,176	34,027
Estimate of fair value measurement
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held-to-maturity securities	1,476	1,600
Loans held-for-sale, net	313	128
Finance receivables and loans, net	120,845	130,837
Federal Home Loan Bank Stock and Federal Reserve Bank Stock	1,000	1,150
Deposit liabilities	61,429	60,678
Short-term borrowings	3,692	5,532
Long-term debt	31,685	36,927
Estimate of fair value measurement \| 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
Federal Home Loan Bank Stock and Federal Reserve Bank Stock	0	0
Deposit liabilities	0	0
Short-term borrowings	0	0
Long-term debt	0	0
Estimate of fair value measurement \| Fair value, inputs, level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held-to-maturity securities	1,476	1,600
Loans held-for-sale, net	0	0
Finance receivables and loans, net	0	0
Federal Home Loan Bank Stock and Federal Reserve Bank Stock	1,000	1,150
Deposit liabilities	0	0
Short-term borrowings	0	0
Long-term debt	19,462	22,789
Estimate of fair value measurement \| 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	313	128
Finance receivables and loans, net	120,845	130,837
Federal Home Loan Bank Stock and Federal Reserve Bank Stock	0	0
Deposit liabilities	61,429	60,678
Short-term borrowings	3,692	5,532
Long-term debt	$ 12,223	$ 14,138

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 of Federal Home Loan Bank (FHLB) and Federal Reserve Bank stock.

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