Mortgage Notes Payable and Credit Facility - Interest Rate Derivatives (Detail) - USD ($) $ in Thousands  | 
9 Months Ended | |
|---|---|---|
Sep. 30, 2020  | 
Dec. 31, 2019  | 
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| Debt Instrument [Line Items] | ||
| Aggregate Cost | $ 1,537 | |
| Aggregate Notional Amount | 187,490 | $ 166,728 | 
| Aggregate Fair Value | $ 17 | 250 | 
| Minimum | LIBOR | ||
| Debt Instrument [Line Items] | ||
| Interest rate (as percent) | 1.50% | |
| Maximum | LIBOR | ||
| Debt Instrument [Line Items] | ||
| Interest rate (as percent) | 3.00% | |
| Interest rate swaps | Counterparty | ||
| Debt Instrument [Line Items] | ||
| Aggregate Notional Amount | $ 62,696 | 45,777 | 
| Aggregate Fair Value | 0 | 0 | 
| Aggregate Fair Value Liability | $ (3,575) | $ (1,173) | 
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available. 
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- Definition Cap rate on an interest rate derivative such as an interest rate cap or collar. If market rates exceed the cap rate, a payment or receipt is triggered on the contract. No definition available. 
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- Definition The premium (cost) of a hedge, expensed during the period. No definition available. 
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- Definition Nominal or face amount used to calculate payment on derivative. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef 
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- Definition Fair value as of the balance sheet date of all interest rate derivative liabilities designated as cash flow hedging instruments. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition Fair value of all derivatives designated as interest rate fair value hedging instruments. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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