Equity Plans and Equity Based Compensation (Additional Information) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2013	Mar. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	481,791
Schedule Of Share Based Compensation Restricted Stock and Restricted Stock Grant During Period Percentage	50.00%
Schedule Of Share Based Compensation Restricted Stock and Restricted Stock Cash Credit Entitlement Percentage	50.00%
Schedule Of Share Based Compensation Restricted Stock and Restricted Stock Vested In Percentage	100.00%
Stock Issued During Period, Shares, Restricted Stock Award, Net of Forfeitures	29,170	32,641
Unrecognized Stock Expenses In Restricted Stock	$ 1,251	$ 981
Share-based Compensation Arrangement by Share-based Payment Award, Discount from Market Price, Offering Date	95.00%
Share Based Compensation Arrangement By Share Based Payment Award Options Vested In Period Percentage		33.30%
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	500,000

Schedule Of Share based Compensation Restricted Stock And Restricted Stock Cash Credit Entitlement Percentage.

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- Definition

Schedule Of Share based Compensation Restricted Stock And Restricted Stock Grant During Period Percentage

+ References

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- Definition

Schedule Of Share based Compensation Restricted Stock And Restricted Stock Vested In Percentage.

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- Definition

Percentage of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

+ References

No definition available.

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- Definition

The Unrecognized expense associated with the restricted stock grants and cash entitlements.

+ References

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- Definition

The discount rate from market value on offering date that participants pay for shares.

+ References

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

-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

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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- Definition

Number of shares issued during the period related to Restricted Stock Awards, net of any shares forfeited.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

-URI http://asc.fasb.org/extlink&oid=6959260&loc=d3e187085-122770

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 129

-Paragraph 4, 5

-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.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 12

-Paragraph 10

-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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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

-Article 5

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

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