Restricted Stock and Stock Options - Additional Information (Detail) $ in Millions	3 Months Ended
Mar. 31, 2021 USD ($) Incentive_Plan shares	Mar. 31, 2020 USD ($) shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of equity incentive plans \| Incentive_Plan	2
Market value of shares \| $		$ 13.7
Stock options exercised, Shares	0
Stock options outstanding	0
Share-based compensation expense \| $	$ 0.6	$ 0.8
Restricted Stock [Member] \| Non-employee Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock issued, shares	0	201
Performance Awards [Member] \| Non-employee Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock issued, shares	0

Number of equity incentive plans.

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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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.

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- Definition

Number of options outstanding, including both vested and non-vested options.

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- Definition

Value, before forfeiture, of shares granted under share-based payment arrangement. Excludes employee stock ownership plan (ESOP).

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Number of share options (or share units) exercised during the current period.

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