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Income Taxes - Additional Information (Detail) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Income Tax [Line Items]
Effective tax rate	25.40%	23.80%	25.00%	23.80%
United States federal statutory income tax rate	21.00%	21.00%	21.00%	21.00%
Unrecognized tax benefits	$ 11,579,000		$ 11,579,000		$ 10,546,000
Unrecognized tax benefits, interest on income taxes accrued	$ 878,000		$ 878,000		$ 749,000
Period during which examination phase of tax audits may conclude, description			Although the timing of the resolutions and/or closures of audits is highly uncertain, it is reasonably possible that the examination phase of these audits may be concluded within the next 12 months, which could increase or decrease the balance of our gross unrecognized tax benefits.
Earliest Tax Year [Member]
Income Tax [Line Items]
Open tax year			2013
Latest Tax Year [Member]
Income Tax [Line Items]
Open tax year			2018

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- Definition

Income Tax [Line Items]

+ References

No definition available.

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- Definition

Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Tax year that remains open to examination under enacted tax laws, in YYYY format.

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This element provides a description of the nature of the event that could occur within twelve months of the reporting date that would cause a significant increase or decrease in the related unrecognized tax benefit.

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Amount of unrecognized tax benefits.

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Amount of interest expense accrued for an underpayment of income taxes.

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