CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Millions	3 Months Ended			9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	[1]	Sep. 30, 2017		Sep. 30, 2016	[1]
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME
Net income	$ 55	$ 60		$ 193	[2]	$ 198
Other comprehensive income
Change in fair value of cash flow hedges (Note 12)		2		1		(1)
Amortization of realized loss on derivative financial instruments (Note 12)				1		1
Reclassification to net income of gains and losses on cash flow hedges (Note 12)	1
Comprehensive income	56	62		195		198
Comprehensive income attributable to non-controlling interests	1	2		7		10
Comprehensive income attributable to controlling interests	$ 55	$ 60		$ 188		$ 188

[1] Recast to consolidate PNGTS for all periods presented (Refer to Notes 2 and 6).

[2] Recast to consolidate PNGTS for all periods presented (Refer to Notes 2 and 6).