Stock-Based Compensation (Details 4) (Restricted Stock Units [Member], USD $)	9 Months Ended	12 Months Ended
Sep. 30, 2012	Dec. 31, 2011
Restricted Stock Units [Member]
Schedule of Restricted Stock Awards
Beginning outstanding balance	407,765	417,923
Awarded	479,911	243,908
Released	(203,519)	(159,384)
Forfeited	(7,402)	(94,682)
Ending outstanding balance	676,755	407,765
Weighted average grant date fair value of RSUs granted	$ 6.78	$ 6.61
Total fair value of RSUs released	$ 1,128,000	$ 1,163,000
Total fair value of RSUs remaining unvested	$ 3,654,000	$ 2,112,000

The total fair value of equity based awards that remain unvested as of the reporting period.

No definition available.

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

+ References

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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 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)

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph c(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Paragraph A240

-Subparagraph b(2)(c)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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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

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)

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-Name Statement of Financial Accounting Standard (FAS)

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-Paragraph A240

-Subparagraph b(2)(b)

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-Name Statement of Financial Accounting Standard (FAS)

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-Paragraph A240

-Subparagraph b(2)(a)

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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- Definition

The total fair value of equity-based awards for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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