Share Repurchase Program - Additional Information (Detail) - Share Repurchase Program [Member] - USD ($)	1 Months Ended	9 Months Ended
Jan. 31, 2021	Jan. 31, 2019	Sep. 30, 2021
Equity Class Of Treasury Stock [Line Items]
Total shares repurchased			38,940
Cost of common stock shares repurchased			$ 18,200,000
Shares repurchase program period		2 years
Shares repurchase program authorized	$ 100,000,000.0	$ 100,000,000.0
Commencement date		2019-04
Share repurchase program, expiration date		Mar. 31, 2021
Share repurchase program, commencement date	Apr. 01, 2021

Share repurchase program commencement date.

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- Definition

Stock repurchase program commencement date.

+ References

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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.

+ References

No definition available.

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- Definition

Amount of stock repurchase plan authorized.

+ References

No definition available.

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- Definition

Expiration date for the purchase of an entity's own shares under a stock repurchase plan, in the YYYY-MM-DD format.

+ References

No definition available.

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- Definition

Period which shares may be purchased under a stock repurchase plan authorized by an entity's Board of Directors, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Number of shares that have been repurchased during the period and are being held in treasury.

+ References

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- Definition

Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

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