Represents the unamortized fair value of award.

No definition available.

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- Definition

Represents the shares withheld to cover federal income taxes.

+ References

No definition available.

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- Definition

Aggregate number of common shares reserved for future issuance.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.29)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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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.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)(iii)(1)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued 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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)(iii)(1)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Per share weighted average intrinsic value of equity-based compensation awards not vested. Excludes stock and unit options.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)(i)-(ii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

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).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(3)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

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.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Description of pertinent provisions of equity-based compensation awards that have actual or potential impact upon the company's financial statements.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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Stock-Based Awards (Details Textual) (USD $)	1 Months Ended			12 Months Ended
Stock-Based Awards (Details Textual) (USD $)	May 31, 2013 Stock Unit Award [Member]	May 31, 2012 Stock Unit Award [Member]	May 31, 2011 Stock Unit Award [Member]	Dec. 31, 2013 Stock Incentive Plan 2006 [Member]	Dec. 31, 2012 Stock Incentive Plan 2006 [Member]	Dec. 31, 2011 Stock Incentive Plan 2006 [Member]	Dec. 31, 2013 Stock Incentive Plan 2006 [Member] Stock Unit Award [Member]	Dec. 31, 2012 Stock Incentive Plan 2006 [Member] Stock Unit Award [Member]	Dec. 31, 2011 Stock Incentive Plan 2006 [Member] Stock Unit Award [Member]	Dec. 31, 2010 Stock Incentive Plan 2006 [Member] Stock Unit Award [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized				500,000
Share-Based Compensation Arrangement By Share-Based Payment Award, Number Of Shares Available For Grant				181,581			181,581
Share-based Compensation Arrangement by Share-based Payment Award, Terms of Award				grants of options with terms of up to ten years
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights	The SUAs vest over a period of two to four years	The SUAs vest over a period of two to four years	The SUAs vest over a period of two to four years				The SUAs vest over a period of two to four years and are convertible into an equivalent number of shares of the Companys common stock provided that the employee receiving the award remains continuously employed throughout the vesting period.
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 11.45	$ 9.79	$ 10.03
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Intrinsic Value, Beginning Balance							$ 14.69	$ 10.75	$ 9.10	$ 8.20
Shares Withheld To Cover Federal Income Taxes							13,362	9,619	8,406
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Unamortized Fair Value							$ 1,057,142
Common Stock, Capital Shares Reserved for Future Issuance				497,506
Share-Based Compensation Arrangement By Share-Based Payment Award, Equity Instruments Other Than Options, Grants In Period				56,500	65,000	59,000	56,500	65,000	59,000