Number of equity incentive plans.

No definition available.

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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

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet 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.

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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).

+ References

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)	3 Months Ended		9 Months Ended
	Sep. 30, 2019 USD ($) shares	Sep. 30, 2018 USD ($)	Sep. 30, 2019 USD ($) Incentive_Plan shares	Sep. 30, 2018 USD ($) shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of equity incentive plans \| Incentive_Plan			2
Stock options outstanding	0		0
Market value of shares \| $			$ 1,500,000	$ 500,000
Stock options exercised, Shares			5,000	15,000
Proceeds from stock option exercises \| $			$ 19,800	$ 66,900
Share-based compensation expense \| $	$ 400,000	$ 300,000	$ 900,000	$ 1,100,000
Restricted Stock [Member] \| Executive Officers [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock issued, shares			11,048
Restricted Stock [Member] \| Non-employee Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock issued, shares			4,890	5,761
Performance Awards [Member] \| Executive Officers [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock issued, shares			9,391	3,304
2005 Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options outstanding	0		0
2005 Incentive Plan [Member] \| Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock outstanding	0		0