Quarterly report pursuant to Section 13 or 15(d)

Borrowings - Summary of Borrowings (Details)

v3.20.1
Borrowings - Summary of Borrowings (Details) - USD ($)
 3 Months Ended
Mar. 31, 2020
Jan. 10, 2020
Dec. 31, 2019
Debt Instrument [Line Items]      
Long-term debt $ 477,526,000   $ 481,929,000
MetLife Facility      
Debt Instrument [Line Items]      
Notes and bonds payable 100,000    
Face amount of debt     200,000,000
Additional available amount $ 24,200,000    
Minimum annualized rate 2.50%    
MetLife Facility | Minimum      
Debt Instrument [Line Items]      
Unused capacity, commitment fee percentage 0.10%    
MetLife Facility | Maximum      
Debt Instrument [Line Items]      
Unused capacity, commitment fee percentage 0.20%    
Mortgage notes and bonds payable      
Debt Instrument [Line Items]      
Notes and bonds payable $ 480,562,000   484,949,000
Debt issuance costs – notes and bonds payable 3,136,000   3,120,000
Long-term debt 477,426,000   481,829,000
Notes payable to bank | MetLife Facility      
Debt Instrument [Line Items]      
Notes and bonds payable 0    
Face amount of debt 75,000,000    
Undrawn commitment 75,000,000   21,530,000
Notes payable to bank | Fixed-rate notes payable      
Debt Instrument [Line Items]      
Notes and bonds payable $ 390,431,000   394,569,000
Notes payable to bank | Fixed-rate notes payable | Minimum      
Debt Instrument [Line Items]      
Stated interest rate (as percent) 3.16%    
Notes payable to bank | Fixed-rate notes payable | Maximum      
Debt Instrument [Line Items]      
Stated interest rate (as percent) 5.70%    
Notes payable to bank | Fixed-rate notes payable | Weighted average      
Debt Instrument [Line Items]      
Stated interest rate (as percent) 4.05%    
Bonds payable | Fixed-rate bonds payable      
Debt Instrument [Line Items]      
Notes and bonds payable $ 90,131,000   90,380,000
Bonds payable | Fixed-rate bonds payable | Minimum      
Debt Instrument [Line Items]      
Stated interest rate (as percent) 2.61%    
Bonds payable | Fixed-rate bonds payable | Maximum      
Debt Instrument [Line Items]      
Stated interest rate (as percent) 4.57%    
Bonds payable | Fixed-rate bonds payable | Weighted average      
Debt Instrument [Line Items]      
Stated interest rate (as percent) 3.44%    
Line of credit | MetLife Facility      
Debt Instrument [Line Items]      
Notes and bonds payable $ 100,000    
Face amount of debt 75,000,000    
Undrawn commitment 74,900,000    
Line of credit | Variable-rate revolving lines of credit | Revolving credit facility      
Debt Instrument [Line Items]      
Long-term debt $ 100,000   $ 100,000
Stated interest rate (as percent) 3.87%    
LIBOR | Line of credit | MetLife Facility      
Debt Instrument [Line Items]      
Basis spread on variable rate 2.00%    
Lease One | Farmer Mac Bonds Payable Issued in Current Period      
Debt Instrument [Line Items]      
Stated interest rate (as percent)   2.66%  
Face amount of debt   $ 8,100,000