Quarterly report pursuant to Section 13 or 15(d)

Borrowings - Summary of Borrowings (Details)

v3.19.3
Borrowings - Summary of Borrowings (Details) - USD ($)
 9 Months Ended
Sep. 30, 2019
Aug. 16, 2019
Dec. 31, 2018
Debt Instrument [Line Items]      
Long-term debt $ 452,104,000   $ 335,888,000
MetLife Facility      
Debt Instrument [Line Items]      
Stated interest rate (as percent)   3.70%  
Face amount of debt 200,000,000    
Additional available amount $ 18,900,000    
Minimum annualized rate 2.50%    
MetLife Facility | Minimum      
Debt Instrument [Line Items]      
Commitment fee percentage 0.10%    
Unused capacity, commitment fee percentage 0.10%    
MetLife Facility | Maximum      
Debt Instrument [Line Items]      
Commitment fee percentage 0.20%    
Unused capacity, commitment fee percentage 0.20%    
Mortgage notes and bonds payable      
Debt Instrument [Line Items]      
Notes and bonds payable $ 450,839,000   338,126,000
Debt issuance costs – notes and bonds payable 2,835,000   2,338,000
Long-term debt 448,004,000   335,788,000
New MetLife Facility      
Debt Instrument [Line Items]      
Notes and bonds payable 142,508,000    
Notes payable to bank | MetLife Facility      
Debt Instrument [Line Items]      
Notes and bonds payable 138,408,000    
Face amount of debt 200,000,000    
Undrawn commitment 47,030,000    
Notes payable to bank | Fixed-rate notes payable      
Debt Instrument [Line Items]      
Notes and bonds payable $ 360,459,000   247,249,000
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) 4.08%    
Notes payable to bank | New MetLife Facility      
Debt Instrument [Line Items]      
Stated interest rate, weighted average (as percent) 3.35%    
Bonds payable | Fixed-rate bonds payable      
Debt Instrument [Line Items]      
Notes and bonds payable $ 90,380,000   90,877,000
Bonds payable | Fixed-rate bonds payable | Minimum      
Debt Instrument [Line Items]      
Stated interest rate (as percent) 2.80%    
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) 3.55%    
Bonds payable | Variable-rate revolving lines of credit | Minimum      
Debt Instrument [Line Items]      
Stated interest rate (as percent) 4.29%    
Bonds payable | Variable-rate revolving lines of credit | Maximum      
Debt Instrument [Line Items]      
Stated interest rate (as percent) 4.54%    
Bonds payable | Variable-rate revolving lines of credit | Weighted average      
Debt Instrument [Line Items]      
Stated interest rate (as percent) 4.29%    
Line of credit | MetLife Facility      
Debt Instrument [Line Items]      
Notes and bonds payable $ 4,100,000    
Face amount of debt 75,000,000    
Undrawn commitment 70,900,000    
Line of credit | Variable-rate revolving lines of credit | Revolving credit facility      
Debt Instrument [Line Items]      
Long-term debt $ 4,100,000   $ 100,000
LIBOR | Line of credit | New MetLife Facility | Minimum      
Debt Instrument [Line Items]      
Basis spread on variable rate 2.00%    
LIBOR | Line of credit | New MetLife Facility | Maximum      
Debt Instrument [Line Items]      
Basis spread on variable rate 2.25%