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

Amount of cash inflow from exercise of option under share-based payment arrangement.

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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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- 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.

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No definition available.

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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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No definition available.

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- Definition

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

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Stock Options and Restricted Stock - Additional Information (Detail) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020 USD ($) shares	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($) Incentive_Plan shares	Sep. 30, 2019 USD ($) shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of equity incentive plans \| Incentive_Plan			2
Market value of shares \| $			$ 1,800	$ 1,500
Stock options exercised, Shares			0	5,000
Proceeds from stock option exercises \| $				$ 20
Stock options outstanding	0		0
Share-based compensation expense \| $	$ 800	$ 400	$ 2,600	$ 900
Restricted Stock [Member] \| Non-employee Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock issued, shares			5,269	4,890
Restricted Stock [Member] \| Executive Officers [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock issued, shares				11,048
Performance Awards [Member] \| Non-employee Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock issued, shares			23,207
Performance Awards [Member] \| Executive Officers [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock issued, shares				9,391