XML 64 R47.htm IDEA: XBRL DOCUMENT v3.22.0.1
Summary of Significant Accounting Policies - Taxes (Details) - USD ($)
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Federal Income Taxes        
Provision for federal or state income taxes $ 0 $ 0 $ 0  
Minimum distribution of taxable income (as a percent) 90.00%      
Distribution percentage 100      
Period considered for calculation of depreciation for federal tax purpose 27 years 6 months      
Period considered for determining the taxability of distributions to shareholders 40 years     30 years
(Excess) / Deficit of book basis of net depreciable assets over tax basis $ 24,983,000