NOTES PAYABLE, FINANCE LEASES, AND COMMERCIAL BANK FINANCING - Notes Payable and Finance Leases to Affiliates, and Debt of VIEs and Guarantees of Third-Party Debt (Details) - USD ($) $ in Millions	Jun. 30, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Current portion of notes payable, finance leases, and commercial bank financing	$ 66	$ 58
Notes payable, finance leases, and commercial bank financing, less current portion	12,473	12,493
Consolidated total debt	12,539
Consolidated VIEs
Debt Instrument [Line Items]
Notes payable, finance leases, and commercial bank financing, less current portion	8	10
Consolidated total debt	14	16
Guarantee Obligations
Debt Instrument [Line Items]
Unconditional and irrevocably guaranteed debt	46	49
Affiliated Entity
Debt Instrument [Line Items]
Current portion of notes payable, finance leases, and commercial bank financing	2	2
Notes payable, finance leases, and commercial bank financing, less current portion	$ 5	$ 6

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

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