ACCOUNTS RECEIVABLE AND OTHER FINANCIAL ASSETS - Summary of the Activity of the Allowance for Expected Credit Losses on Prepayments to Customers (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Contract With Customer, Asset, Prepayments To Customers, Allowance for Credit Loss [Abstract]
Balance, beginning of year	$ 55	$ 6
Provision charged to expense	(2)	49
Write-offs and adjustments	(3)	(1)
Balance, end of period	$ 50	$ 54