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Subsequent Events - Additional Information (Details) $ / shares in Units, $ in Thousands |  |  |  |  | 9 Months Ended
--- | --- | --- | --- | --- | ---
Oct. 28, 2019 USD ($) $ / shares shares | Oct. 04, 2019 USD ($) $ / shares shares | Oct. 02, 2019 USD ($) property | Jan. 31, 2019 mortgage | Sep. 30, 2019 USD ($) mortgage | Sep. 30, 2018 USD ($)
Subsequent Event [Line Items] |  |  |  |  |  |
Proceeds from issuance of equity |  |  |  |  | $ 41,231 | $ 12,504
Fixed rate mortgage loans |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |
Number of long-term mortgages repaid | mortgage |  |  |  | 3 | 1 |
Stated interest rate (as percent) |  |  |  |  | 4.18% |
Subsequent event | Fixed rate mortgage loans |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |
Number of long-term mortgages repaid | property |  |  | 1 |  |  |
Carrying value |  |  | $ 6,300 |  |  |
Stated interest rate (as percent) |  |  | 6.00% |  |  |
Series E Preferred Stock | Subsequent event |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |
Stock issued during period, shares | shares |  | 2,760,000 |  |  |  |
Shares issued, price per share | $ / shares |  | $ 25.00 |  |  |  |
Stock issued during period, amount |  | $ 69,000 |  |  |  |
Proceeds from issuance of equity |  | $ 66,600 |  |  |  |
Series A Preferred Stock | Subsequent event |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |
Stock redeemed during period, shares | shares | 1,000,000 |  |  |  |  |
Preferred stock, redemption price per share | $ / shares | $ 25.1506944 |  |  |  |  |
Series B Preferred Stock | Subsequent event |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |
Stock redeemed during period, shares | shares | 1,264,000 |  |  |  |  |
Preferred stock, redemption price per share | $ / shares | $ 25.1458333 |  |  |  |  |
Series A and B Preferred Stock | Subsequent event |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |
Aggregate redemption price | $ 56,900 |  |  |  |  |

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