Lease Agreements and Power Purchase Agreements - Additional Information (Details)	9 Months Ended
Aug. 31, 2017 Lease
Operating Leased Assets [Line Items]
Estimated residual value over the lease term (in years)	20 years
Residential Portfolio
Operating Leased Assets [Line Items]
Number of solar homeowners	5,800

Term of the lessor's leasing arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration