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Equity Compensation Plans (Narrative) (Details) shares in Thousands, $ in Thousands | 9 Months Ended
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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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