Related Parties - First Solar ROFO Agreement (Details) - MW				12 Months Ended
	Aug. 11, 2017	May 15, 2017	Feb. 13, 2017	Nov. 30, 2017
Related Party Transaction [Line Items]
Power purchase agreement serving (in years)				5 years
MW(ac)				946
Switch Station Solar Generation Project | OpCo
Related Party Transaction [Line Items]
MW(ac)				179
Cuyama Solar Generation Project | OpCo
Related Party Transaction [Line Items]
MW(ac)				40
California Flats Solar Generation Project | OpCo
Related Party Transaction [Line Items]
MW(ac)				280
First Solar ROFO Agreement | OpCo
Related Party Transaction [Line Items]
Power purchase agreement serving (in years)				5 years
Negotiation period (in days)	45 days	45 days	45 days