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Equity Incentive Plan - Additional Information (Details)
1 Months Ended 3 Months Ended 12 Months Ended
Mar. 01, 2021
$ / shares
shares
Mar. 01, 2020
shares
Mar. 01, 2019
shares
Mar. 01, 2018
shares
Mar. 01, 2017
shares
Jan. 28, 2016
shares
May 17, 2013
shares
Jan. 31, 2021
shares
Jan. 31, 2020
shares
Mar. 31, 2021
USD ($)
shares
Mar. 31, 2020
USD ($)
Dec. 31, 2020
USD ($)
shares
Independent Trustees                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                        
Common share issued as compensation for services performed (in shares)               40,224 24,516      
Equity Incentive Plan                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                        
Number of shares authorized (in shares)             3,000,000          
Common shares available for issuance (in shares)                   589,804    
Equity Incentive Plan | Minimum                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                        
Vesting period for share awards under equity             3 years          
Equity Incentive Plan | Maximum                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                        
Vesting period for share awards under equity             5 years          
Restricted Stock                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                        
Unrecognized compensation costs | $                   $ 21,300   $ 28,500
Weighted-average period for recognition of unrecognized compensation costs                   8 months 12 days    
Compensation expense, recognized | $                   $ 7,200 $ 8,300  
Number of shares, Granted (in shares)                   0   0
Long Term Incentive Plan Units                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                        
Weighted-average period for recognition of unrecognized compensation costs                   2 years 3 months 18 days    
Compensation expense, recognized | $                   $ 1,000,000.0 $ 1,400,000  
Exchange ratio                   1    
Number of shares, Granted (in shares)                   330,945   325,507
Total unrecognized compensation cost related to LTIP Units | $                   $ 8,600,000   $ 4,900,000
Time-Based LTIP Unit Awards                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                        
Number of shares, Granted (in shares) 132,381 130,206 88,746 97,968 89,574 72,966            
Time-Based LTIP Unit Awards | Awarded March 1, 2021                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                        
Number of shares, Granted (in shares) 132,381                      
Performance-Based LTIP Unit Awards                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                        
Number of shares, Granted (in shares) 198,564 195,301 133,107 146,949 134,348 39,285            
Performance-Based LTIP Unit Awards | Awarded March 1, 2021                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                        
Number of shares, Granted (in shares) 198,564                      
Grants in period, intrinsic value, amount per share (in dollars per share) | $ / shares $ 15.91                      
Performance-Based LTIP Unit Awards | Awarded March 1, 2021 | Minimum                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                        
Percentage of units paid out   50.00%                    
Performance-Based LTIP Unit Awards | Awarded March 1, 2021 | Maximum                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                        
Percentage of units paid out   150.00%