| Summary of Changes in Stockholders' Equity | 
 The following table summarizes the changes in our equity for the three and nine months ended September 30, 2020 and 2019 (in thousands): 
  
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Three Months Ended September 30, | 
 | 
Nine Months Ended September 30, | 
 
| Series A and B Preferred Stock | 
2020 | 
2019 | 
 | 
2020 | 
2019 | 
 
| Balance, beginning of period | 
$ | 
—  | 
 | 
$ | 
2  | 
 | 
 | 
$ | 
—  | 
 | 
$ | 
2  | 
 | 
 
| Issuance of Series A and B preferred stock, net | 
—  | 
 | 
—  | 
 | 
 | 
—  | 
 | 
—  | 
 | 
 
| Balance, end of period | 
$ | 
—  | 
 | 
$ | 
2  | 
 | 
 | 
$ | 
—  | 
 | 
$ | 
2  | 
 | 
 
| Senior Common Stock | 
 | 
 | 
 | 
 | 
 | 
 
| Balance, beginning of period | 
$ | 
1  | 
 | 
$ | 
1  | 
 | 
 | 
$ | 
1  | 
 | 
$ | 
1  | 
 | 
 
| Issuance of senior common stock, net | 
—  | 
 | 
—  | 
 | 
 | 
—  | 
 | 
—  | 
 | 
 
| Balance, end of period | 
$ | 
1  | 
 | 
$ | 
1  | 
 | 
 | 
$ | 
1  | 
 | 
$ | 
1  | 
 | 
 
| Common Stock | 
 | 
 | 
 | 
 | 
 | 
 
| Balance, beginning of period | 
$ | 
34  | 
 | 
$ | 
31  | 
 | 
 | 
$ | 
32  | 
 | 
$ | 
29  | 
 | 
 
| Issuance of common stock, net | 
—  | 
 | 
—  | 
 | 
 | 
2  | 
 | 
2  | 
 | 
 
| Balance, end of period | 
$ | 
34  | 
 | 
$ | 
31  | 
 | 
 | 
$ | 
34  | 
 | 
$ | 
31  | 
 | 
 
| Series F Preferred Stock (1) | 
 | 
 | 
 | 
 | 
 | 
 
| Balance, beginning of period | 
$ | 
—  | 
 | 
$ | 
—  | 
 | 
 | 
$ | 
—  | 
 | 
$ | 
—  | 
 | 
 
| Issuance of Series F preferred stock, net | 
—  | 
 | 
—  | 
 | 
 | 
—  | 
 | 
—  | 
 | 
 
| Balance, end of period | 
$ | 
—  | 
 | 
$ | 
—  | 
 | 
 | 
$ | 
—  | 
 | 
$ | 
—  | 
 | 
 
| Additional Paid in Capital | 
 | 
 | 
 | 
 | 
 | 
 
| Balance, beginning of period | 
$ | 
599,741  | 
 | 
$ | 
592,706  | 
 | 
 | 
$ | 
571,205  | 
 | 
$ | 
559,977  | 
 | 
 
| Issuance of common stock and Series F preferred stock, net (1) | 
5,027  | 
 | 
7,362  | 
 | 
 | 
33,465  | 
 | 
40,608  | 
 | 
 
 | 
 | 
 | 
 | 
 | 
 | 
 
| Adjustment to OP Units held by Non-controlling OP Unitholders resulting from changes in ownership of the Operating Partnership | 
(61) | 
 | 
(112) | 
 | 
 | 
37  | 
 | 
(629) | 
 | 
 
| Balance, end of period | 
$ | 
604,707  | 
 | 
$ | 
599,956  | 
 | 
 | 
$ | 
604,707  | 
 | 
$ | 
599,956  | 
 | 
 
| Accumulated Other Comprehensive Income | 
 | 
 | 
 | 
 | 
 | 
 
| Balance, beginning of period | 
$ | 
(5,135) | 
 | 
$ | 
(1,859) | 
 | 
 | 
$ | 
(2,126) | 
 | 
$ | 
(148) | 
 | 
 
| Comprehensive income | 
276  | 
 | 
(624) | 
 | 
 | 
(2,733) | 
 | 
(2,335) | 
 | 
 
| Balance, end of period | 
$ | 
(4,859) | 
 | 
$ | 
(2,483) | 
 | 
 | 
$ | 
(4,859) | 
 | 
$ | 
(2,483) | 
 | 
 
| Distributions in Excess of Accumulated Earnings | 
 | 
 | 
 | 
 | 
 | 
 
| Balance, beginning of period | 
$ | 
(388,900) | 
 | 
$ | 
(331,461) | 
 | 
 | 
$ | 
(360,978) | 
 | 
$ | 
(310,117) | 
 | 
 
| Distributions declared to common, senior common, and preferred stockholders | 
(15,780) | 
 | 
(14,482) | 
 | 
 | 
(46,965) | 
 | 
(42,674) | 
 | 
 
| Net income attributable to the Company | 
2,846  | 
 | 
2,207  | 
 | 
 | 
6,109  | 
 | 
9,055  | 
 | 
 
| Balance, end of period | 
$ | 
(401,834) | 
 | 
$ | 
(343,736) | 
 | 
 | 
$ | 
(401,834) | 
 | 
$ | 
(343,736) | 
 | 
 
| Total Stockholders' Equity | 
 | 
 | 
 | 
 | 
 | 
 
| Balance, beginning of period | 
$ | 
205,741  | 
 | 
$ | 
259,420  | 
 | 
 | 
$ | 
208,134  | 
 | 
$ | 
249,744  | 
 | 
 
| Issuance of common stock and Series F preferred stock, net (1) | 
5,027  | 
 | 
7,362  | 
 | 
 | 
33,467  | 
 | 
40,610  | 
 | 
 
 | 
 | 
 | 
 | 
 | 
 | 
 
| Distributions declared to common, senior common, and preferred stockholders | 
(15,780) | 
 | 
(14,482) | 
 | 
 | 
(46,965) | 
 | 
(42,674) | 
 | 
 
| Comprehensive income | 
276  | 
 | 
(624) | 
 | 
 | 
(2,733) | 
 | 
(2,335) | 
 | 
 
| Adjustment to OP Units held by Non-controlling OP Unitholders resulting from changes in ownership of the Operating Partnership | 
(61) | 
 | 
(112) | 
 | 
 | 
37  | 
 | 
(629) | 
 | 
 
| Net income attributable to the Company | 
2,846  | 
 | 
2,207  | 
 | 
 | 
6,109  | 
 | 
9,055  | 
 | 
 
| Balance, end of period | 
$ | 
198,049  | 
 | 
$ | 
253,771  | 
 | 
 | 
$ | 
198,049  | 
 | 
$ | 
253,771  | 
 | 
 
| Non-Controlling Interest | 
 | 
 | 
 | 
 | 
 | 
 
| Balance, beginning of period | 
$ | 
2,892  | 
 | 
$ | 
4,665  | 
 | 
 | 
$ | 
2,903  | 
 | 
$ | 
4,675  | 
 | 
 
| Distributions declared to Non-controlling OP Unit holders | 
(189) | 
 | 
(279) | 
 | 
 | 
(567) | 
 | 
(835) | 
 | 
 
| Issuance of Non-controlling OP Units as consideration in real estate acquisitions, net | 
—  | 
 | 
—  | 
 | 
 | 
502  | 
 | 
—  | 
 | 
 
| Adjustment to OP Units held by Non-controlling OP Unitholders resulting from changes in ownership of the Operating Partnership | 
61  | 
 | 
112  | 
 | 
 | 
(37) | 
 | 
629  | 
 | 
 
| Net (loss) income (attributable) available to OP units held by Non-controlling OP Unitholders | 
(2) | 
 | 
(16) | 
 | 
 | 
(39) | 
 | 
13  | 
 | 
 
| Balance, end of period | 
$ | 
2,762  | 
 | 
$ | 
4,482  | 
 | 
 | 
$ | 
2,762  | 
 | 
$ | 
4,482  | 
 | 
 
| Total Equity | 
$ | 
200,811  | 
 | 
$ | 
258,253  | 
 | 
 | 
$ | 
200,811  | 
 | 
$ | 
258,253  | 
 | 
 
 
(1)No shares of Series F Preferred Stock were outstanding prior to July 1, 2020
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