Consolidated Statements of Comprehensive Income (Loss) (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Statement of Comprehensive Income [Abstract]
Net loss	$ (1,774)	$ (14,684)	$ (14,394)	$ (12,145)
Other comprehensive income (loss):
Foreign currency translation, net of zero tax impact	(13,346)	7,286	(22,448)	9,749
Derivative activity:
Effective portion of change in fair market value of derivatives, net of tax benefit (provision) of $100, ($98), $1,046 and ($59), respectively	4,991	(3,877)	8,736	(4,418)
Reclassifications to net loss due to de-designation of interest rate derivatives, net of zero tax impact	(1,529)	0	(1,529)	0
Reclassifications to net loss, net of tax impact of $74, $236, $339 and $487, respectively	1,222	2,164	2,618	4,483
Total change in effective portion of change in fair value of derivatives	4,684	(1,713)	9,825	65
Proportionate share of equity investee’s derivative activity:
Effective portion of change in fair market value of derivatives, net of tax provision of ($184), ($1,064), ($475) and ($285), respectively	509	2,950	1,317	790
Reclassifications to net loss, net of tax impact of $408, $629, $898 and $1,661, respectively	1,129	1,747	2,489	4,608
Total change in effective portion of change in fair value of derivatives	1,638	4,697	3,806	5,398
Total other comprehensive income (loss), net of tax	(7,024)	10,270	(8,817)	15,212
Comprehensive income (loss)	(8,798)	(4,414)	(23,211)	3,067
Less comprehensive income (loss) attributable to noncontrolling interest:
Net loss attributable to noncontrolling interest	(34,492)	(28,904)	(183,034)	(32,018)
Foreign currency translation, net of zero tax impact	(1,286)	0	(2,913)	0
Derivative activity:
Effective portion of change in fair market value of derivatives, net of tax benefit (provision) of $42, $93, ($108) and $101, respectively	375	(253)	981	(274)
Reclassifications to net gain due to de-designation of interest rate derivatives, net of zero tax impact	(447)	0	(447)	0
Reclassifications to net loss, net of tax impact of ($25), $29, $3 and $62, respectively	280	79	627	167
Total change in effective portion of change in fair value of derivatives	208	(174)	1,161	(107)
Comprehensive loss attributable to noncontrolling interest	(35,570)	(29,078)	(184,786)	(32,125)
Comprehensive income attributable to Pattern Energy	$ 26,772	$ 24,664	$ 161,575	$ 35,192