Equity Compensation Plans (Narrative) (Details) shares in Thousands, $ in Thousands	9 Months Ended
Sep. 30, 2015 USD ($) shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Description of participants purchase limit	Participants may not purchase more than $25 of the Company's common stock in a calendar year and, effective January 1, 2014, may not purchase more than 3 shares during an offering period.
Participants purchase limit shares	3
Offering period	6 months
2001 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expiry of options from the date of grant	10 years
2005 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expiry of options from the date of grant	10 years
2014 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for issuance	8,949
Expiry of options from the date of grant	10 years
2008 Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Company's common stock may be purchased at a discount	15.00%
Participants purchase limit value \| $	$ 25
Shares available for sale under the ESPP increased	2.00%
Outstanding shares of common stock exceed	600
Shares available for future issuance under the ESPP	524
Employee Stock Option [Member] \| 2005 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercisable period beginning	3 years
Employee Stock Option [Member] \| 2005 Plan [Member] \| First Anniversary Date Of Grant And Ratably Each Month Thereafter For Three Years [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual vesting percentage	25.00%
Employee Stock Option [Member] \| 2014 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercisable period beginning	3 years
Employee Stock Option [Member] \| 2014 Plan [Member] \| First Anniversary Date Of Grant And Ratably Each Month Thereafter For Three Years [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual vesting percentage	25.00%
Restricted Stock [Member] \| 2005 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted from the 2005 Plan generally vest	4 years
Restricted Stock [Member] \| 2005 Plan [Member] \| Four Years From Date Of Grant [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual vesting percentage	25.00%
Restricted Stock [Member] \| 2014 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted from the 2005 Plan generally vest	4 years
Restricted Stock [Member] \| 2014 Plan [Member] \| Four Years From Date Of Grant [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual vesting percentage	25.00%

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Option one percentage of outstanding shares.

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Share based compensation arrangement by share based payment award maximum value per employee.

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Aggregate number of common shares reserved for future issuance.

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-Publisher FASB

-Name Accounting Standards Codification

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Number of common shares reserved for future issuance related to deferred compensation arrangements with individuals.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Discount rate from fair value on purchase date that participants pay for shares.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The highest quantity of shares an employee can purchase under the plan per period.

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Description of significant modifications (such as a change in expiration dating, vesting rights, or exercise prices) to an equity-based compensation plan, including the terms of the modifications.

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Percentage of vesting of share-based compensation awards.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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