Number Of Companies Used For Estimation Of Expected Volatility

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Share based compensation arrangement by share based payment award equity instruments other than options increase in annual award.

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Amount of paid and unpaid cash dividends declared and applicable to holders of share-based compensation, for example, but not limited to, non-vested shares, stock options, or restricted stock units.

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Amount of cash inflow from realized tax benefit related to deductible compensation cost reported on the entity's tax return for equity instruments in excess of the compensation cost for those instruments recognized for financial reporting purposes.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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).

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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.

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The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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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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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Stock Options and Restricted Stock - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2018 USD ($) Company shares	Dec. 31, 2017 USD ($) shares	Dec. 31, 2016 USD ($) shares	Dec. 31, 2013 USD ($)	Dec. 31, 2015 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total tax expense			$ 995,000
2005 Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Duration for Stock option grants exercisable	10 years
Expiration of stock option	90 days
Unexercised portion of stock option remains exercisable	1 year
Number of companies used for the estimation of expected volatility \| Company	6
Dividend yield assumed	0.00%
Cash dividends paid				$ 0
Compensation expense	$ 12,000	$ 56,000	58,000
Total tax expense	$ 0	$ 0	$ 110,000
2005 Incentive Plan [Member] \| Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock outstanding \| shares			800		1,600
2012 Equity and Incentive Compensation Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized under incentive plan \| shares	500,000
Common stock granted \| shares	3,304	7,434
Common stock available for future awards \| shares	343,147
2012 Equity and Incentive Compensation Plan [Member] \| Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock granted \| shares		1,892
2012 Equity and Incentive Compensation Plan [Member] \| Share Based Grants [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	$ 726,000	$ 884,000	$ 849,000
2012 Equity and Incentive Compensation Plan [Member] \| Long-Term Incentive Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	976,000	724,000	334,000
Non-Employee Director Restricted Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	351,000	355,000	361,000
Total tax expense	$ 0	$ 0	$ 52,000
Shares authorized under incentive plan \| shares	150,000
Common stock granted \| shares	5,761	6,454	5,952
Common stock available for future awards \| shares	57,907
Restricted stock award for a number of shares	$ 50,000
Restricted stock outstanding \| shares	5,761	6,454	5,576		7,112
Non-Employee Director Restricted Stock Plan [Member] \| Restricted Stock [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Increase in annual restricted stock award	$ 75,000