Description of Business - Summary of Assets Comprise the Portfolio (Details)	3 Months Ended	12 Months Ended
	Feb. 28, 2018 Lease MW	Nov. 30, 2017	Jun. 09, 2017 MW	Feb. 24, 2017 MW	Nov. 30, 2016 MW	Sep. 09, 2016 MW	Jan. 26, 2016 MW
Description Of Business And Basis Of Presentation [Line Items]
MW(ac)	946
Maryland Solar | Maryland | FirstEnergy Solutions
Description Of Business And Basis Of Presentation [Line Items]
MW(ac)	20
Remaining term of offtake agreement (in years)	15 years 1 month 6 days
Solar Gen 2 | California | SDG&E
Description Of Business And Basis Of Presentation [Line Items]
MW(ac)	150
Remaining term of offtake agreement (in years)	21 years 8 months 12 days
Lost Hills Blackwell | California | City of Roseville/PG&E
Description Of Business And Basis Of Presentation [Line Items]
MW(ac)	32
Remaining term of offtake agreement (in years)	25 years 9 months 18 days
Lost Hills Blackwell | California | PG&E
Description Of Business And Basis Of Presentation [Line Items]
Remaining term of offtake agreement (in years)		25 years
Lost Hills Blackwell | California | City Of Roseville
Description Of Business And Basis Of Presentation [Line Items]
Remaining term of offtake agreement (in years)	9 months 19 days
North Star | California | PG&E
Description Of Business And Basis Of Presentation [Line Items]
MW(ac)	60
Remaining term of offtake agreement (in years)	17 years 3 months 18 days
RPU | California | City of Riverside
Description Of Business And Basis Of Presentation [Line Items]
MW(ac)	7
Remaining term of offtake agreement (in years)	22 years 7 months 6 days
Quinto | California | Southern California Edison
Description Of Business And Basis Of Presentation [Line Items]
MW(ac)	108
Remaining term of offtake agreement (in years)	17 years 9 months 18 days
Hooper | Colorado | Public Service Company of Colorado
Description Of Business And Basis Of Presentation [Line Items]
MW(ac)	50
Remaining term of offtake agreement (in years)	17 years 9 months 18 days
Kingbird | California | Southern California Public Power Authority
Description Of Business And Basis Of Presentation [Line Items]
MW(ac)	40
Remaining term of offtake agreement (in years)	18 years 2 months 12 days
Henrietta | California | PG&E
Description Of Business And Basis Of Presentation [Line Items]
MW(ac)	102
Remaining term of offtake agreement (in years)	18 years 7 months 6 days
Stateline | California | Southern California Edison
Description Of Business And Basis Of Presentation [Line Items]
MW(ac)	300
Remaining term of offtake agreement (in years)	18 years 6 months
UC Davis | California | University of California
Description Of Business And Basis Of Presentation [Line Items]
MW(ac)	13
Remaining term of offtake agreement (in years)	17 years 6 months
Macy's California | California | Macy's Corporate Services
Description Of Business And Basis Of Presentation [Line Items]
MW(ac)	3
Remaining term of offtake agreement (in years)	17 years 8 months 12 days
Macy’s Maryland | Maryland | Macy's Corporate Services
Description Of Business And Basis Of Presentation [Line Items]
MW(ac)	5
Remaining term of offtake agreement (in years)	18 years 9 months 18 days
Kern | California | Kern High School District
Description Of Business And Basis Of Presentation [Line Items]
MW(ac)	18
Remaining term of offtake agreement (in years)	19 years
Residential Portfolio
Description Of Business And Basis Of Presentation [Line Items]
Number of solar installations | Lease	5,800
Residential Portfolio | U.S. – Various
Description Of Business And Basis Of Presentation [Line Items]
Number of solar installations | Lease	5,800
Residential Portfolio | U.S. – Various | Homeowners
Description Of Business And Basis Of Presentation [Line Items]
MW(ac)	38
Remaining term of offtake agreement (in years)	14 years 6 months
OpCo | Kern | California
Description Of Business And Basis Of Presentation [Line Items]
MW(ac)			2	3	5	5	3