Share Based Compensation (Narratvie-ESPP) (Details) (USD $)	12 Months Ended
Dec. 31, 2014
Employee Stock Purchase 1999 Plan [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	3,500,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	1,378,369
Employee share purchase plan offering period, months	0 years 6 months 0 days
Amended Employee Stock Purchase 1999 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Discount rate for employee stock purchase plan	5.00%
Employee share purchase plan offering period, months	0 years 6 months 0 days
Maximum employee gross compensation withheld to purchase common stock	5.00%
Maximum fair value of common stock purchased by employee each calendar year	25,000
Maxium dollar contribution to ESPP	5,000

The percent discount provided to eligible employees on shares purchased under the Employee Stock Purchase Plan.

No definition available.

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- Definition

Employee Share Purchase Plan Offering Period, Months

+ References

No definition available.

+ Details

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- Definition

Reflects the maximum fair value of common stock that eligible employees are permitted to purchase under the Employee Stock Purchase Plan.

+ References

No definition available.

+ Details

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- Definition

The highest dollar amount that an employee is permitted to utilize with respect to the plan.

+ References

No definition available.

+ Details

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- Definition

The highest percentage of annual salary that an employee is permitted to utilize with respect to the 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

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

+ Details

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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

+ Details

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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

+ Details

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- Details

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