Quarterly report pursuant to Section 13 or 15(d)

Equity - Additional Information (Details)

v3.19.3
Equity - Additional Information (Details)
 3 Months Ended 9 Months Ended 12 Months Ended 30 Months Ended 50 Months Ended
Jul. 18, 2019
USD ($)
Jul. 16, 2019
shares
Jun. 20, 2019
USD ($)
$ / shares
shares
May 31, 2018
USD ($)
$ / shares
shares
Apr. 12, 2017
USD ($)
security
Sep. 30, 2019
USD ($)
$ / shares
shares
Sep. 30, 2019
USD ($)
$ / shares
shares
Sep. 30, 2018
USD ($)
shares
Dec. 31, 2018
USD ($)
$ / shares
shares
Sep. 30, 2019
USD ($)
$ / shares
shares
Sep. 30, 2019
USD ($)
$ / shares
shares
Jun. 30, 2019
shares
Jun. 30, 2018
shares
Jan. 10, 2018
shares
Jan. 09, 2018
shares
Dec. 31, 2017
shares
Aug. 07, 2015
USD ($)
Subsidiary, Sale of Stock [Line Items]                                  
Stock authorized and unissued (in shares) | shares                           6,500,000      
Common stock, shares authorized (in shares) | shares           91,500,000 91,500,000   91,500,000 91,500,000 91,500,000     91,500,000 98,000,000    
Preferred stock, liquidation value           $ 86,600,000 $ 86,600,000   $ 28,600,000 $ 86,600,000 $ 86,600,000            
Common stock, par value (in dollars per share) | $ / shares           $ 0.001 $ 0.001   $ 0.001 $ 0.001 $ 0.001            
Common stock, shares issued (in shares) | shares           20,888,075 20,888,075   17,891,340 20,888,075 20,888,075            
Common stock, shares outstanding (in shares) | shares           20,888,075 20,888,075   17,891,340 20,888,075 20,888,075            
Maximum number of securities that can be sold (in securities) | security         2                        
Proceeds from issuance of preferred and common equity             $ 86,070,000 $ 34,397,000                  
Discounts and offering expenses             6,551,000 $ 1,894,000                  
Redemptions of Series B Preferred Stock           $ 48,000 $ 214,000                    
June 2019 Offering                                  
Subsidiary, Sale of Stock [Line Items]                                  
Securities allowed for issuance (amount up to)     $ 23,500,000                            
Maximum amount authorized in Primary Offering (in shares) | shares     2,000,000                            
Proceeds from issuance of preferred stock     $ 22,300,000                            
Average sales price price (in dollars per share) | $ / shares     $ 11.73                            
Over-Allotment Option                                  
Subsidiary, Sale of Stock [Line Items]                                  
Net proceeds from issuance of stock $ 3,100,000                                
Number of shares sold (in shares) | shares   277,297                              
Gross proceeds $ 3,300,000                                
2017 Registration Statement                                  
Subsidiary, Sale of Stock [Line Items]                                  
Proceeds from issuance of preferred and common equity                   $ 96,100,000              
Common Stock                                  
Subsidiary, Sale of Stock [Line Items]                                  
Common stock, par value (in dollars per share) | $ / shares           $ 0.001 $ 0.001   $ 0.001 $ 0.001 $ 0.001            
Common stock, shares issued (in shares) | shares           20,888,075 20,888,075   17,891,340 20,888,075 20,888,075            
Common stock, shares outstanding (in shares) | shares           20,888,075 20,888,075 16,070,616 17,891,340 20,888,075 20,888,075 20,532,770 16,023,872     13,791,574  
Common Stock | 2017 Registration Statement                                  
Subsidiary, Sale of Stock [Line Items]                                  
Common stock, shares issued (in shares) | shares           7,821,886 7,821,886     7,821,886 7,821,886            
Securities allowed for issuance (amount up to)         $ 300,000,000                        
Stock Redeemed | shares                   1,215,565              
Series B Preferred Stock                                  
Subsidiary, Sale of Stock [Line Items]                                  
Preferred stock, shares authorized (in shares) | shares           6,500,000 6,500,000   6,500,000 6,500,000 6,500,000            
Preferred stock, par value (in dollars per share) | $ / shares           $ 0.001 $ 0.001   $ 0.001 $ 0.001 $ 0.001            
Preferred stock, shares issued (in shares) | shares           3,465,527 3,465,527   1,144,393 3,465,527 3,465,527            
Preferred stock, shares outstanding (in shares) | shares           3,465,527 3,465,527   1,144,393 3,465,527 3,465,527            
Series B Preferred Stock | 2017 Registration Statement                                  
Subsidiary, Sale of Stock [Line Items]                                  
Proceeds from issuance of preferred and common equity                   $ 85,600,000              
Series B Preferred Stock | Preferred Stock                                  
Subsidiary, Sale of Stock [Line Items]                                  
Preferred stock, shares outstanding (in shares) | shares           3,465,527 3,465,527 393,048 1,144,393 3,465,527 3,465,527 2,636,068 20,280     0  
Redemption price (in dollars per share) | $ / shares           $ 22.50 $ 22.50     $ 22.50 $ 22.50            
Securities allowed for issuance (amount up to)       $ 150,000,000                          
Maximum amount authorized in Primary Offering (in shares) | shares       6,000,000                          
Dividend rate (as percent)       6.00%                          
Average sales price of common stock sold (in dollars per share) | $ / shares       $ 25                          
Proceeds from issuance of preferred stock       $ 131,300,000                          
Stock Redeemed | shares           2,120 9,520                    
Discounts and offering expenses             $ 1,200,000                    
Net proceeds from issuance of stock           $ 18,711,000 52,440,000                    
Redemptions of Series B Preferred Stock           $ 48,000 $ 214,000                    
Number of shares sold (in shares) | shares           831,579 2,330,654                    
Weighted-average Offering Price Per Share | $ / shares           $ 24.64 $ 24.68                    
Gross proceeds           $ 20,487,000 $ 57,529,000                    
Series B Preferred Stock | Preferred Stock | 2017 Registration Statement                                  
Subsidiary, Sale of Stock [Line Items]                                  
Common stock, shares issued (in shares) | shares           3,475,047 3,475,047     3,475,047 3,475,047            
Common Stock                                  
Subsidiary, Sale of Stock [Line Items]                                  
Net proceeds from issuance of stock                     $ 22,000,000            
Number of shares sold (in shares) | shares                     1,744,150            
Weighted-average Offering Price Per Share | $ / shares                     $ 12.82            
Gross proceeds                     $ 22,400,000            
Common Stock | ATM Program                                  
Subsidiary, Sale of Stock [Line Items]                                  
Net proceeds from issuance of stock           $ 923,000 $ 1,802,000                    
Common stock, value authorized                                 $ 30,000,000.0
Number of shares sold (in shares) | shares           78,008 148,559                    
Weighted-average Offering Price Per Share | $ / shares           $ 12.01 $ 12.32                    
Gross proceeds           $ 937,000 $ 1,830,000                    
OP Unit Holder                                  
Subsidiary, Sale of Stock [Line Items]                                  
Company's ownership percent (as percent)           98.60% 98.60%   96.90% 98.60% 98.60%            
Minimum period required to exercise, in months             12 months                    
Gladstone Land Limited Partnership                                  
Subsidiary, Sale of Stock [Line Items]                                  
OP units held by non-controlling limited partners (in shares) | shares             288,303   570,879