Annual report pursuant to Section 13 and 15(d)

Subsequent Events (Details)

v3.20.4
Subsequent Events (Details)
12 Months Ended
Mar. 12, 2021
USD ($)
Feb. 17, 2021
USD ($)
$ / shares
shares
Feb. 02, 2021
USD ($)
Aug. 01, 2020
USD ($)
Feb. 07, 2019
USD ($)
Jan. 11, 2019
USD ($)
Jan. 01, 2019
Dec. 31, 2020
USD ($)
a
Mar. 11, 2021
$ / shares
shares
Jan. 26, 2021
USD ($)
Dec. 23, 2020
USD ($)
Dec. 22, 2020
USD ($)
$ / shares
shares
Dec. 31, 2019
USD ($)
Apr. 08, 2016
$ / shares
shares
Subsequent Event [Line Items]                            
Loans payable, net               $ 334,266,000         $ 340,913,000  
Line of Credit                            
Subsequent Event [Line Items]                            
Loans payable, net               1,100,000            
Common stock shares under warrants issued (in shares) | shares                           750,000
Exercise price of warrants (in usd per share) | $ / shares                           $ 0.0001
Powerscourt Financing Agreement                            
Subsequent Event [Line Items]                            
Common stock shares under warrants issued (in shares) | shares                       496,415    
Exercise price of warrants (in usd per share) | $ / shares                       $ 3.12    
Powerscourt Financing Agreement | Line of Credit                            
Subsequent Event [Line Items]                            
Loans payable, net               $ 25,000,000       $ 25,000,000.00 0  
Debt interest rate               13.50%       13.50%    
Berkley Shopping Center                            
Subsequent Event [Line Items]                            
Area of land | a               0.75            
Riversedge North | Disposal Group, Disposed of by Sale, Not Discontinued Operations                            
Subsequent Event [Line Items]                            
Contract price               $ 3,000,000            
Series D Preferred Stock                            
Subsequent Event [Line Items]                            
Preferred stock cumulative dividend rate per annum             10.75%              
Series D Preferred Stock | Minimum                            
Subsequent Event [Line Items]                            
Preferred stock cumulative dividend rate per annum               8.75%            
Series D Preferred Stock | Modified Dutch Auction                            
Subsequent Event [Line Items]                            
Stock repurchase program, authorized amount                     $ 19,000,000.00      
Tuckernuck                            
Subsequent Event [Line Items]                            
Loans payable, net               $ 5,193,000         $ 5,344,000  
Debt interest rate               3.88%            
Debt periodic payment       $ 34,000       $ 33,880            
Revere Term Loan                            
Subsequent Event [Line Items]                            
Debt periodic payment         $ 30,000 $ 323,000                
Subsequent Event | Powerscourt Financing Agreement | Line of Credit                            
Subsequent Event [Line Items]                            
Loans payable, net $ 25,000,000.00                          
Subsequent Event | Wilmington Financing Agreement                            
Subsequent Event [Line Items]                            
Common stock shares under warrants issued (in shares) | shares                 1,061,719          
Subsequent Event | Wilmington Financing Agreement | Wilmington Agreement Group 1                            
Subsequent Event [Line Items]                            
Common stock shares under warrants issued (in shares) | shares                 510,204          
Exercise price of warrants (in usd per share) | $ / shares                 $ 3.43          
Subsequent Event | Wilmington Financing Agreement | Wilmington Agreement Group 2                            
Subsequent Event [Line Items]                            
Common stock shares under warrants issued (in shares) | shares                 424,242          
Exercise price of warrants (in usd per share) | $ / shares                 $ 4.125          
Subsequent Event | Wilmington Financing Agreement | Wilmington Agreement Group 3                            
Subsequent Event [Line Items]                            
Common stock shares under warrants issued (in shares) | shares                 127,273          
Exercise price of warrants (in usd per share) | $ / shares                 $ 6.875          
Subsequent Event | Wilmington Financing Agreement | Line of Credit                            
Subsequent Event [Line Items]                            
Loans payable, net $ 35,000,000.00                          
Debt interest rate 8.00%                          
Premium, percentage of principal payment 5.00%                          
Subsequent Event | Series D Preferred Stock | Minimum                            
Subsequent Event [Line Items]                            
Preferred stock cumulative dividend rate per annum 8.75%                          
Subsequent Event | Series D Preferred Stock | Modified Dutch Auction                            
Subsequent Event [Line Items]                            
Stock repurchase program, authorized amount   $ 6,000,000.00               $ 20,000,000.00        
Number of shares authorized to be repurchased (in shares) | shares   387,097                        
Purchase price (in usd per share) | $ / shares   $ 15.50                        
Aggregate cost of shares repurchased   $ 6,000,000.00                        
Subsequent Event | Tuckernuck                            
Subsequent Event [Line Items]                            
Loans payable, net     $ 5,150,000                      
Debt interest rate     5.00%                      
Debt periodic payment     $ 32,000