Other Assets and Other Liabilities and Deferred Income (Details) - USD ($) $ in Millions	Sep. 30, 2020	Jan. 01, 2020	Dec. 31, 2019
Other Assets and Other Liabilities [Abstract]
Accrued interest and other non-finance receivables	$ 1,799		$ 898
Collateral held for resale, at net realizable value, and other inventory	623		843
Prepaid Reinsurance Premiums and Other Reinsurance Recoverables	705		687
Deferred charges - income taxes	151		171
Property and equipment, net of accumulated depreciation	213		212
Operating lease assets	100		108
Investment in non-consolidated affiliates	132		132
Other	409		347
Total other assets	4,132	$ 3,390	3,398
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	412		393
Unearned Premiums and Fees	822		806
Interest Payable	670		888
Taxes Payable	144		433
Deferred Revenue	91		110
Operating Lease, Liability	102		110
Other Liabilities	2,097		2,633
Related Party Transactions Income Taxes and Related Interest Payable	15		294
Other Liabilities, Miscellaneous	268		286
Parent [Member]
Other Assets and Other Liabilities [Abstract]
Income Taxes Receivable	959		0
Accounting Standards Update 2016-13 [Member]
Other Assets and Other Liabilities [Abstract]
Investment in non-consolidated affiliates		(8)
Total other assets		$ (8)
Property Subject to Operating Lease [Member]
Other Assets and Other Liabilities [Abstract]
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	$ 5,840		$ 5,772