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Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2021 | Jun. 30, 2020 | Jun. 30, 2021 | Jun. 30, 2020 | Dec. 31, 2020
Income Tax Disclosure [Line Items] |  |  |  |  |
Effective tax rate expense (benefit) | 18.10% | 68.50% | 26.70% | 22.90% |
Income tax benefit, result of CARES act of 2020 |  |  |  | $ 7,400 |
Income tax expense, result of Alabama business tax competitiveness act |  |  | $ 1,600 |  |
Deferred tax assets, gross | $ 56,941 |  | 56,941 |  | $ 55,687
Valuation allowance established against deferred tax assets | 47,776 |  | 47,776 |  | 45,818
Deferred tax assets | 9,165 |  | 9,165 |  | 9,869
Domestic [Member] |  |  |  |  |
Income Tax Disclosure [Line Items] |  |  |  |  |
Valuation allowance established against deferred tax assets |  |  | 1,600 |  |
Deferred tax assets, gross | 45,383 |  | 45,383 |  | 43,791
Valuation allowance established against deferred tax assets | $ 45,383 |  | $ 45,383 |  | $ 43,791

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