Accumulated Other Comprehensive Income (Loss) (Tables)

9 Months Ended

Sep. 30, 2020

Equity [Abstract]

Schedule of accumulated other comprehensive income (loss)

	Accumulated Other Comprehensive Income (Loss)
	Net Unrealized Gains on Cash Flow Hedges		Other Comprehensive Income (Loss) Related to Equity Method Investees		Total
	(millions)
Balances, December 31, 2019	$	—	$	(22)	$	(22)
Net other comprehensive income (loss)	—		—		—
Balances, March 31, 2020	—		(22)		(22)
Other comprehensive income related to equity method investee	—		1		1
Net other comprehensive income	—		1		1
Balances, June 30, 2020	—		(21)		(21)
Net other comprehensive income (loss)	—		—		—
Balances, September 30, 2020	$	—	$	(21)	$	(21)
AOCI attributable to noncontrolling interest	$	—	$	(13)	$	(13)
AOCI attributable to NEP	$	—	$	(8)	$	(8)

	Accumulated Other Comprehensive Income (Loss)
	Net Unrealized Gains on Cash Flow Hedges		Other Comprehensive Income (Loss) Related to Equity Method Investee		Total
	(millions)
Balances, December 31, 2018	$	6	$	(24)	$	(18)
Amounts reclassified from AOCI to interest expense	(6)		—		(6)
Other comprehensive income related to equity method investee	—		1		1
Net other comprehensive income (loss)	(6)		1		(5)
Balances, March 31, 2019	—		(23)		(23)
Net other comprehensive income (loss)	—		—		—
Balances, June 30, 2019	—		(23)		(23)
Net other comprehensive income (loss)	—		—		—
Balances, September 30, 2019	$	—	$	(23)	$	(23)
AOCI attributable to noncontrolling interest	$	—	$	(15)	$	(15)
AOCI attributable to NEP	$	—	$	(8)	$	(8)