Stock-Based Compensation (Stock Option Activity) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	9 Months Ended
Sep. 30, 2013
Number of Stock Options:
Outstanding, beginning of period (in shares)	394,322
Granted (in shares)	47,000
Exercised (in shares)	(41,637)
Canceled/Forfeited (in shares)	(9,833)
Expired (in shares)	0
Outstanding, end of period (in shares)	389,852
Exercisable (in shares)	326,770
Weighted Average Exercise Price:
Outstanding, weighted average exercise price, beginning of period (in USD per share)	$ 15.30
Granted, weighted average exercise price (in USD per share)	$ 18.75
Exercised, weighted average exercise price (in USD per share)	$ 15.38
Canceled/Forfeited, weighted average exercise price (in USD per share)	$ 17.68
Expired, weighted average exercise price (in USD per share)	$ 0.00
Outstanding, weighted average exercise price, end of period (in USD per share)	$ 15.65
Exercisable, weighted average exercise price (in USD per share)	$ 15.22
Options, Weighted Average Remaining Contractual Term:
Outstanding, weighted average remaining contractual life	5 years 5 months 27 days
Exercisable, weighted average remaining contractual life	4 years 9 months 26 days
Options, Intrinsic Value:
Outstanding, aggregate intrinsic value	$ 4,355
Exercisable, aggregate intrinsic value	$ 3,790

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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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.

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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.

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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.

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Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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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.

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Gross number of share options (or share units) granted during the period.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of options outstanding, including both vested and non-vested options.

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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.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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