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v3.20.4

Subsequent Events - Additional Information (Detail) |  |  | 2 Months Ended | 12 Months Ended |  |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Feb. 11, 2021 USD ($) | Jan. 22, 2021 USD ($) ft² tenant | Feb. 16, 2021 USD ($) shares | Dec. 31, 2020 USD ($) shares | Jul. 02, 2019 USD ($) | Jul. 01, 2019 USD ($) | Oct. 27, 2017 USD ($) | Oct. 26, 2017 USD ($) | Oct. 31, 2015 USD ($)
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |
Rent obligations deferred, percentage |  |  |  | 2.00% |  |  |  |  |
Line of credit facility, maximum borrowing capacity |  |  |  |  | $ 160,000,000.0 | $ 75,000,000.0 | $ 75,000,000.0 | $ 25,000,000.0 |
Line of credit |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |
Line of credit facility, maximum borrowing capacity |  |  |  |  |  |  |  |  | $ 85,000,000.0
Subsequent Event | New Term Loan Facility |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |
Line of credit facility, maximum borrowing capacity | $ 65,000,000.0 |  |  |  |  |  |  |  |
Line of credit facility, delayed funding component | $ 15,000,000.0 |  |  |  |  |  |  |  |
Subsequent Event | New Term Loan Facility | LIBOR |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |
Floor on LIBOR (as percent) | 0.25% |  |  |  |  |  |  |  |
Subsequent Event | New Term Loan Facility | Line of credit |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |
Debt instrument term | 60 months |  |  |  |  |  |  |  |
Subsequent Event | Property Maturing February 15, 2031 | New fixed rate mortgage notes payable |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |
Debt issued |  | $ 5,500,000 |  |  |  |  |  |  |
Stated interest rate (as a percent) |  | 3.24% |  |  |  |  |  |  |
Subsequent Event | Findlay, Ohio |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |
Aggregate Square Footage | ft² |  | 180,152 |  |  |  |  |  |  |
Payments to acquire real estate |  | $ 11,100,000 |  |  |  |  |  |  |
Number of tenants | tenant |  | 1 |  |  |  |  |  |  |
Lease term |  | 14 years 2 months 12 days |  |  |  |  |  |  |
Common Stock | Subsequent Event |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |
Net proceeds from sale of shares |  |  | $ 6,800,000 |  |  |  |  |  |
Number of shares sold (in shares) | shares |  |  | 400,000 |  |  |  |  |  |
Preferred Stock | Series F Preferred Stock |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |
Net proceeds from sale of shares |  |  |  | $ 2,700,000 |  |  |  |  |
Number of shares sold (in shares) | shares |  |  |  | 100,000 |  |  |  |  |
Preferred Stock | Series F Preferred Stock | Subsequent Event |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |
Net proceeds from sale of shares |  |  | $ 30,000.00 |  |  |  |  |  |
Number of shares sold (in shares) | shares |  |  | 1,200 |  |  |  |  |  |

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