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Plan's Benefit Obligations, Fair Value of Plan Assets, and Funded Status (Detail) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Compensation And Retirement Disclosure [Abstract] |  |
Benefit Obligation | $ 385 | $ 326
Fair value of plan assets | 452 | 411
Defined Benefit Plan, Funded Status of Plan | (67) | (85)
Noncurrent liabilities (assets) | (67) | (85)
Net amount recognized | (67) | (85)
Amounts recognized in accumulated comprehensive income (loss) consist of: |  |
Unrecognized net gain (loss) | $ (94) | $ (66)

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