Quarterly report pursuant to Section 13 or 15(d)

Our Portfolio - Additional Information (Detail)

v3.5.0.2
Our Portfolio - Additional Information (Detail)
 1 Months Ended 3 Months Ended 6 Months Ended
Jun. 30, 2016
USD ($)
MW
Jun. 30, 2016
USD ($)
Jun. 30, 2015
USD ($)
Jun. 30, 2016
USD ($)
Jun. 30, 2015
USD ($)
Dec. 31, 2015
USD ($)
Financing Receivable, Recorded Investment [Line Items]            
Financing receivables, investments, real estate and equity method investments $ 1,391,000,000 $ 1,391,000,000   $ 1,391,000,000    
Deferred funding obligations 78,127,000 78,127,000   78,127,000   $ 108,499,000
Investment securities pledged as collateral $ 42,000,000 42,000,000   42,000,000    
Total megawatts power acquired from third party | MW 43          
Payments to acquire projects $ 33,000,000          
Investment amount $ 42,000,000 42,000,000   42,000,000    
Non interest bearing period 2 years          
Financing receivables on non accrual status $ 0 0   0   $ 0
Loan modifications that qualify as trouble debt restructurings   0 $ 0 0 $ 0  
Provision for credit losses   $ 0 $ 0 $ 0 $ 0  
Minimum [Member]            
Financing Receivable, Recorded Investment [Line Items]            
Long-term triple net leases expiration dates range       2033    
Long-term triple net leases extended expiration dates range       2047    
Maximum [Member]            
Financing Receivable, Recorded Investment [Line Items]            
Long-term triple net leases expiration dates range       2051    
Long-term triple net leases extended expiration dates range       2080