LONG-TERM DEBT LONG-TERM DEBT - SECURED DEBT (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Debt instrument, increase (decrease)	$ (604)
Long-term Debt	1,499	$ 2,103
Long-term debt payments	1,058	807	$ 397
Repayments of debt	779
Proceeds from Issuance of Debt	450	$ 339	$ 0
Variable Rate debt with interest rate swap [Member]
Debt Instrument [Line Items]
Long-term Debt	$ 717

Net increase or decrease in the carrying amount of the debt instrument for the period.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
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-Section S99
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

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The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

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