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Income Taxes - Additional Information (Detail) - USD ($) $ in Millions | 9 Months Ended
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Sep. 30, 2021 | Sep. 30, 2020
Income Tax Disclosure [Abstract] |  |
Effective change in income tax rate | 20.60% | 21.00%
Discrete benefit for research and development tax credits | $ 2.9 |
Discrete benefit from change in tax status of subsidiary from partnership to corporation |  | $ 6.9

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- Definition Effective income tax percentage reconciliation change in reclassification from partnership to corporation. + References No definition available. + Details
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- Definition Effective income tax rate reconciliation change in reclassification from partnership to corporation. + References No definition available. + Details
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- Definition Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to research tax credit. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32687-109319 + Details
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