FINANCIAL CHARGES AND OTHER (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
FINANCIAL CHARGES AND OTHER
Interest Expense	$ 95	$ 83	$ 69
Net realized loss related to the interest rate swaps	(2)		3
PNGTS' amortization of realized loss on derivative instrument (Note 20)	1	1	1
Other	(2)	(2)	(2)
Financial charges and other	$ 92	$ 82	$ 71	[1]

[1] Recast to consolidate PNGTS (Refer to Notes 2 and 8).