v3.20.2

Interest Rate Swaps - Summary of Interest-rate Swap Agreements (Parenthetical) (Detail) - Interest Rate Swap - M&T Bank - USD ($) | 6 Months Ended |
--- | --- | ---
Jun. 30, 2020 | Dec. 31, 2019
Derivative [Line Items] |  |
Notional Amount | $ 4,841,000 | $ 4,912,000
Umbrella Partnership Real Estate Investment Trust Transaction |  |
Derivative [Line Items] |  |
Interest rate swap assumed month and year | 2017-10 |

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