COMMITMENTS AND CONTINGENCIES - Contingencies (Details) - USD ($) $ in Millions	Jun. 30, 2021	Dec. 31, 2020
Commitments and Contingencies Disclosure [Abstract]
Environmental obligations	$ 159	$ 135
Less: current portion	15	18
Long-term environmental obligations	$ 144	$ 117

Carrying value of the obligation (known or estimated) arising from requirements to perform activities to remediate one or more sites, payable in twelve months or in the next operating cycle if longer.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section S99
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-Subparagraph (SX 210.5-02.20)
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
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