NATURE OF OPERATIONS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Supplemental Information - Statement of Cash Flows (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Income taxes paid	$ 32	$ 17	$ 128
Income tax refunds	2	0	2
Interest paid	283	285	204
Non- cash transactions
Non-cash transaction property and equipment	$ 10	$ 11	$ 10

Future cash outflow to pay for purchases of fixed assets that have occurred.

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The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income.

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The amount of cash received during the period as refunds for the overpayment of taxes.

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