| **Stockholders' Equity (Summary of Option activity under the Stock Option Plan) (Details) (USD $)In Thousands, except Per Share data, unless otherwise specified** | 9 Months Ended    |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------|-------------------|
||
| **Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]**                                                         |              |
| Outstanding, beginning (Shares)                                                                                                                                    | 1,087             |
| Exercised (Shares)                                                                                                                                                 | (284)             |
| Forfeited (Shares)                                                                                                                                                 | (14)              |
| Expired (Shares)                                                                                                                                                   | (33)              |
| Outstanding, ending (Shares)                                                                                                                                       | 756               |
| Exercisable (Shares)                                                                                                                                               | 712               |
| **Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price [Rollforward]**                            |              |
| Oustanding, beginning (Weighted Average Exercise Price)                                                                                                            | $ 7.27            |
| Exercised (Weighted Average Exercise Price)                                                                                                                        | $ 6.78            |
| Forfeited (Weighted Average Exercise Price)                                                                                                                        | $ 5.86            |
| Expired (Weighted Average Exercise Price)                                                                                                                          | $ 5.83            |
| Oustanding, ending (Weighted Average Exercise Price)                                                                                                               | $ 7.54            |
| Exercisable (Weighted Average Exercise Price)                                                                                                                      | $ 7.59            |
| Outstanding, Weighted Average Contractual Term                                                                                                                     | 3 years 10 months |
| Exercisable, Weighted Average Contractual Term                                                                                                                     | 3 years 8 months  |
| Outstanding, Aggregated Intrinsic Value                                                                                                                            | $ 1,795           |
| Exercisable, Aggregated Intrinsic Value                                                                                                                            | $ 1,660           |

| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.
+ References
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| - Definition
Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.
+ References
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|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Weighted average price at which option holders acquired shares when converting their stock options into shares.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                              |
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| - Definition
Weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired.
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| - Definition
Weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that were forfeited.
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| - Definition
The total dollar difference between fair values of the underlying shares reserved for issuance and exercise prices of vested portions of options outstanding and currently exercisable under the option plan as of the balance sheet date.
+ References
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| - Definition
The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.
+ References
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| - Definition
The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.
+ References
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| - Definition
The decrease in the number of shares that could be issued attributable to the lapse of rights to exercise previously issued stock options under the terms of the option agreements under the plan during the reporting period.
+ References
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| - Definition
The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.
+ References
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The total dollar difference between fair values of the underlying shares reserved for issuance and exercise prices pertaining to options outstanding under the plan as of the balance sheet date.
+ References
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|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The number of shares reserved for issuance under stock option agreements awarded under the plan that validly exist and are outstanding as of the balance sheet date, including vested options.
+ References
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|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The weighted average price as of the beginning of the year at which grantees can acquire the shares reserved for issuance under the stock option plan.
+ References
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|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Number of share options (or share units) exercised during the current period.
+ References
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