| Derivative Financial Instruments - Effect of Derivative Financial Instruments that are Not Designated as Hedging Instruments on Income Statement (Detail) - Not Designated as Hedging Instrument - USD ($) | 12 Months Ended | |
|---|---|---|
| Dec. 31, 2020 | Dec. 31, 2019 | |
| Derivative Instruments Gain Loss [Line Items] | ||
| Amount of Gain or (Loss) Recognized in Income on Derivative | $ (61,000) | $ 0 | 
| Interest Rate Products | Other Income | ||
| Derivative Instruments Gain Loss [Line Items] | ||
| Amount of Gain or (Loss) Recognized in Income on Derivative | $ (61,000) | |
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- Definition Amount of increase (decrease) in the fair value of derivatives recognized in the income statement. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef 
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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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