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Stock-Based Compensation (Stock Options by Exercise Price Range) (Details)	9 Months Ended
	Sep. 30, 2015 $ / shares shares
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options outstanding, shares | shares	417,269
Options outstanding, weighted average remaining contractual life (in years)	5 years 3 months 22 days
Options outstanding, weighted average exercise price (in USD per share)	$ 19.06
Options exercisable, shares | shares	313,766
Options exercisable, weighted average exercise price (in USD per share)	$ 17.10
$0.01-15.70
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options outstanding, shares | shares	94,852
Options outstanding, weighted average remaining contractual life (in years)	3 years 4 months 52 days
Options outstanding, weighted average exercise price (in USD per share)	$ 11.23
Options exercisable, shares | shares	94,852
Options exercisable, weighted average exercise price (in USD per share)	$ 11.23
Range of exercise prices, lower limit (in USD per share)	0.01
Range of exercise prices, upper limit (in USD per share)	$ 15.70
$15.71-17.81
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options outstanding, shares | shares	95,250
Options outstanding, weighted average remaining contractual life (in years)	3 years 9 months 66 days
Options outstanding, weighted average exercise price (in USD per share)	$ 17.55
Options exercisable, shares | shares	95,250
Options exercisable, weighted average exercise price (in USD per share)	$ 17.55
Range of exercise prices, lower limit (in USD per share)	15.71
Range of exercise prices, upper limit (in USD per share)	$ 17.81
$17.82-20.48
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options outstanding, shares | shares	119,667
Options outstanding, weighted average remaining contractual life (in years)	4 years 5 months 37 days
Options outstanding, weighted average exercise price (in USD per share)	$ 19.58
Options exercisable, shares | shares	106,167
Options exercisable, weighted average exercise price (in USD per share)	$ 19.69
Range of exercise prices, lower limit (in USD per share)	17.82
Range of exercise prices, upper limit (in USD per share)	$ 20.48
$20.49-33.36
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options outstanding, shares | shares	107,500
Options outstanding, weighted average remaining contractual life (in years)	9 years
Options outstanding, weighted average exercise price (in USD per share)	$ 26.72
Options exercisable, shares | shares	17,497
Options exercisable, weighted average exercise price (in USD per share)	$ 30.69
Range of exercise prices, lower limit (in USD per share)	20.49
Range of exercise prices, upper limit (in USD per share)	$ 33.36

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The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ References

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-Name Accounting Standards Codification



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The number of shares reserved for issuance pertaining to the outstanding exercisable stock options as of the balance sheet date in the customized range of exercise prices for which the market and performance vesting condition has been satisfied.

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The number of shares reserved for issuance pertaining to the outstanding stock options as of the balance sheet date for all option plans in the customized range of exercise prices.

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Weighted average exercise price as of the balance sheet date for those equity-based payment arrangements exercisable and outstanding.

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The weighted average price as of the balance sheet date at which grantees could acquire the underlying shares with respect to all outstanding stock options which are in the customized range of exercise prices.

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Weighted average remaining contractual term of outstanding stock options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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