DEBT AND CREDIT FACILITIES - Principal Payments Required (Details) $ in Millions	Dec. 31, 2018 USD ($)
Principal repayments required on debt
2019	$ 36
2020	123
2021	440
2022	500
2023	19
Thereafter	1,000
Total debt	$ 2,118

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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-SubTopic 10
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