Quarterly report pursuant to Section 13 or 15(d)

Summary of Significant Accounting Policies - Credit Risk Classification (Details)

v3.20.1
Summary of Significant Accounting Policies - Credit Risk Classification (Details) - USD ($)
$ in Thousands
Mar. 31, 2020
Dec. 31, 2019
Investing Receivables    
Financing Receivable, Credit Quality Indicator [Line Items]    
2015 and Earlier $ 62,853  
2016 0  
2017 866  
2018 0  
2019 11,076  
2020 0  
Total as of March 31, 2020 74,795 $ 73,523
Investing Receivables | Investment grade    
Financing Receivable, Credit Quality Indicator [Line Items]    
2015 and Earlier 59,833  
2016 0  
2017 866  
2018 0  
2019 0  
2020 0  
Total as of March 31, 2020 60,699  
Investing Receivables | Non-investment grade    
Financing Receivable, Credit Quality Indicator [Line Items]    
2015 and Earlier 3,020  
2016 0  
2017 0  
2018 0  
2019 11,076  
2020 0  
Total as of March 31, 2020 14,096  
Tenant Notes Receivables    
Financing Receivable, Credit Quality Indicator [Line Items]    
2015 and Earlier 118  
2016 297  
2017 0  
2018 1,285  
2019 2,179  
2020 0  
Total as of March 31, 2020 3,879  
Tenant Notes Receivables | Investment grade    
Financing Receivable, Credit Quality Indicator [Line Items]    
2015 and Earlier 21  
2016 78  
2017 0  
2018 1,100  
2019 100  
2020 0  
Total as of March 31, 2020 1,299  
Tenant Notes Receivables | Non-investment grade    
Financing Receivable, Credit Quality Indicator [Line Items]    
2015 and Earlier 97  
2016 219  
2017 0  
2018 185  
2019 2,079  
2020 0  
Total as of March 31, 2020 $ 2,580