NOTES PAYABLE, FINANCE LEASES, AND COMMERCIAL BANK FINANCING - Accounts Receivable Securitization Facility (Details) - USD ($)	Oct. 22, 2020	Sep. 30, 2020	Sep. 23, 2020	Dec. 31, 2019
Line of Credit Facility [Line Items]
Accounts receivable, net		$ 1,108,000,000		$ 1,132,000,000
Line of Credit Facility | A/R Facility
Line of Credit Facility [Line Items]
Maximum borrowing capacity			$ 250,000,000
Maximum borrowing capacity, addition			50,000,000
Aggregate outstanding principal amount of loans (less than)			$ 125,000,000
Prepayment premium (as a percent)			1.00%
Borrowings outstanding		74,000,000
Line of Credit Facility | A/R Facility | Floor
Line of Credit Facility [Line Items]
Interest rate (as a percent)			0.00%
Line of Credit Facility | A/R Facility | LIBOR
Line of Credit Facility [Line Items]
Interest rate before November 1, 2020 (as a percent)			4.97%
Interest rate after November 1, 2020 (as a percent)			5.47%
Line of Credit Facility | A/R Facility | DSPV
Line of Credit Facility [Line Items]
Accounts receivable, net		$ 124,000,000
Line of Credit Facility | A/R Facility | Subsequent Event
Line of Credit Facility [Line Items]
Borrowings outstanding	$ 196,000,000
Additional funding from credit facility	$ 122,000,000