Quarterly report pursuant to Section 13 or 15(d)

Our Portfolio - Analysis of Portfolio by Type of Obligor and Credit Quality (Footnotes) (Details)

v3.19.2
Our Portfolio - Analysis of Portfolio by Type of Obligor and Credit Quality (Footnotes) (Details)
6 Months Ended
Jun. 30, 2019
USD ($)
transaction
Dec. 31, 2018
USD ($)
Financing Receivable, Credit Quality Indicator [Line Items]    
Financing receivables on non accrual status $ 0 $ 0
Number of transactions | transaction 175  
Financial receivable outstanding $ 9,000,000  
Total aggregate remaining balance 63,000,000  
Maximum [Member]    
Financing Receivable, Credit Quality Indicator [Line Items]    
Financial receivable outstanding 1,000,000  
Commercial Non-Investment Grade [Member]    
Financing Receivable, Credit Quality Indicator [Line Items]    
Increase in finance receivables 16,000,000  
Financial receivable outstanding 15,000,000  
Special Purpose Subsidiaries [Member]    
Financing Receivable, Credit Quality Indicator [Line Items]    
Noncontrolling equity investments 24,000,000  
Investment Grade by Independent Rating Agency [Member]    
Financing Receivable, Credit Quality Indicator [Line Items]    
Total financing receivable 9,000,000  
U.S. Federal Government [Member]    
Financing Receivable, Credit Quality Indicator [Line Items]    
Total financing receivable 228,000,000  
State, Local, Institutions [Member]    
Financing Receivable, Credit Quality Indicator [Line Items]    
Total financing receivable 155,000,000  
Residential Solar Loan [Member]    
Financing Receivable, Credit Quality Indicator [Line Items]    
Loans receivable 328,000,000  
Residential Solar Loan [Member] | Special Purpose Subsidiaries [Member]    
Financing Receivable, Credit Quality Indicator [Line Items]    
Loans receivable $ 206,000,000