Equity Plans and Equity Based Compensation - Additional Information (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of equity incentive plans			3
Shares of common stock reserved for future issuance	611,548		611,548
Options granted in period			0	0
Compensation expense related to option grants	$ 0	$ 0	$ 0	$ 0
Unrecognized compensation cost related to option grants	0	0	0	0
Long-term incentive awards, vested description			The restricted stock grants and tandem cash credit entitlements are subject to forfeiture in the event that the recipient of the grant does not continue employment with the Company through December 5 of the year of grant, at which time they generally vest 100 percent.
Vesting percentage			100.00%
Unrecognized expense associated with the restricted stock grants and cash entitlements	304	296	304	296
Purchase price of shares as percentage of fair market value of Company's common stock			95.00%
Number of shares provided for purchase under Employee Stock Purchase Plan			500,000
Expense recorded for employee stock purchase plan	0	0	0	0
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense related to option grants	155	158	463	466
Incentive award percentage			50.00%
Stock awards granted	118	302	30,137	37,769
Cash Entitlement [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense related to option grants	$ 147	$ 138	$ 440	$ 413
Incentive award percentage			50.00%

Employee Purchase Plan Purchase Price Percentage of Fair Market Value

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Employee Stock Purchase Plan Compensation Expense

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Employee Stock Purchase Plan, Maximum Number Of Shares That May Be Purchased By Eligible Participants

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- Definition

Number of Plans

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Percentage of Award by Type of Award

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- Definition

Share Based Compensation Arrangement by Share based Payment Award, Vesting Percentage

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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- Definition

Aggregate number of common shares reserved for future issuance.

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- Definition

Aggregate unrecognized cost of share-based awards, other than options, made to employees under an equity-based compensation plan, that have yet to vest.

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- Definition

Aggregate unrecognized cost of option awards made to employees under a stock option plan or plans, that have yet to vest.

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- Definition

Description of award terms as to how many shares or portion of an award are no longer contingent on satisfaction of either a service condition, market condition or a performance condition, thereby giving the employee the legal right to convert the award to shares, to sell the shares, and be entitled to the cash proceeds of such sale. For example, vesting may be expressed as being 25 percent of the shares under option on each anniversary of the grant date.

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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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Net number of share options (or share units) granted during the period.

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