NOTES PAYABLE AND COMMERCIAL BANK FINANCING - Debt of Variable Interest Entities and Guarantees of Third-party Debt (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Debt and lease obligations	$ 12,551
Consolidated VIEs
Debt Instrument [Line Items]
Debt and lease obligations	$ 16	$ 20
LIBOR \| Debt of variable interest entities
Debt Instrument [Line Items]
Basis spread on variable rate	2.50%
Guarantee Obligations
Debt Instrument [Line Items]
Unconditional and irrevocably guaranteed debt	$ 49	$ 57

Amount of short-term and long-term debt and lease obligation.

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