Summary of Significant Accounting and Reporting Policies - Noncontrolling Interests (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Balances, beginning of period	$ 4,883,000
Net income (loss) attributable to NCI	(500,000)	$ (105,000)
Related party contributions	3,000	1,000
Related party distributions	(62,000)	(51,000)
Changes in non-economic ownership interests		(6,000)
Payments to Class B noncontrolling interests investors	(10,000)	(5,000)
Other	(1,000)	1,000
Balances, end of period	4,354,000
Noncontrolling Ownership Interests In NEP OpCo Subsidiary [Member]
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Balances, beginning of period	2,628,000	751,000
Net income (loss) attributable to NCI	52,000	12,000
Payments to Class B noncontrolling interests investors	(10,000)	(5,000)
Balances, end of period	2,670,000	758,000
Differential Membership Interests [Member]
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Balances, beginning of period	1,798,000	2,019,000
Net income (loss) attributable to NCI	(71,000)	(60,000)
Differential membership interests contributions, net of distributions	40,000	24,000
Balances, end of period	1,767,000	1,983,000
Noncontrolling Ownership Interests in NEP OpCo, Texas Pipeline and Silver State [Member]
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Balances, beginning of period	389,000	342,000
Net income (loss) attributable to NCI	(459,000)	(50,000)
Other comprehensive income (loss)		(3,000)
Related party contributions		1,000
Related party distributions	(60,000)	(50,000)
Other		1,000
Balances, end of period	(130,000)	241,000
Other Noncontrolling Interest [Member]
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Balances, beginning of period	68,000	80,000
Net income (loss) attributable to NCI	(22,000)	(7,000)
Other comprehensive income (loss)		0
Related party contributions	3,000
Related party distributions	(2,000)	(1,000)
Changes in non-economic ownership interests		(6,000)
Balances, end of period	47,000	66,000
Non-controlling Interests [Member]
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Balances, beginning of period	4,883,000	3,192,000
Net income (loss) attributable to NCI	(500,000)	(105,000)
Other comprehensive income (loss)		(3,000)
Related party contributions	3,000	1,000
Related party distributions	(62,000)	(51,000)
Changes in non-economic ownership interests		(6,000)
Differential membership interests contributions, net of distributions	40,000	24,000
Payments to Class B noncontrolling interests investors	(10,000)	(5,000)
Other		1,000
Balances, end of period	$ 4,354,000	$ 3,048,000