Other Assets and Other Liabilities and Deferred Income (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Jan. 01, 2020	Dec. 31, 2019
Other Assets and Other Liabilities [Abstract]
Accrued interest and other non-finance receivables	$ 847			$ 898
Collateral held for resale, at net realizable value, and other inventory	803			843
Prepaid Reinsurance Premiums and Other Reinsurance Recoverables	689			687
Deferred charges - income taxes	168			171
Property and equipment, net of accumulated depreciation	212			212
Operating lease assets	103			108
Investment in non-consolidated affiliates	(126)			(132)
Other	354			347
Total other assets	3,302		$ 3,390	3,398
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	396			393
Provision for Other Credit Losses	586	$ 33
Unearned Premiums and Fees	805			806
Interest Payable	608			888
Taxes Payable	212			433
Deferred Revenue	103			110
Operating Lease, Liability	105			110
Other Liabilities, Miscellaneous	250			286
Other Liabilities	2,083			2,633
Related Party Transactions Income Taxes and Related Interest Payable	75			294
Accounting Standards Update 2016-13 [Member]
Other Assets and Other Liabilities [Abstract]
Investment in non-consolidated affiliates			8
Total other assets			$ (8)
Global Pandemic Impact [Member]
Other Assets and Other Liabilities [Abstract]
Provision for Other Credit Losses	5
Property Subject to Operating Lease [Member]
Other Assets and Other Liabilities [Abstract]
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	5,819			$ 5,772
Property Subject to Operating Lease [Member] | Global Pandemic Impact [Member]
Other Assets and Other Liabilities [Abstract]
Collateral held for resale, at net realizable value, and other inventory	59
Adverse impact [Member]
Other Assets and Other Liabilities [Abstract]
Loss on Contract Termination for Default	54
Provision for Other Credit Losses	$ 486