Stock-Based Compensation (Stock Options by Exercise Price Range) (Details) (USD $)	3 Months Ended
Mar. 31, 2015
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options outstanding, shares	380,769
Options outstanding, weighted average remaining contractual life (in years)	5 years 1 month 30 days
Options outstanding, weighted average exercise price (in USD per share)	$ 18.52
Options exercisable, shares	325,599
Options exercisable, weighted average exercise price (in USD per share)	$ 17.05
$0.01-15.70
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options outstanding, shares	95,852
Options outstanding, weighted average remaining contractual life (in years)	3 years 10 months 45 days
Options outstanding, weighted average exercise price (in USD per share)	$ 11.26
Options exercisable, shares	95,852
Options exercisable, weighted average exercise price (in USD per share)	$ 11.26
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	102,750
Options outstanding, weighted average remaining contractual life (in years)	4 years 5 months 8 days
Options outstanding, weighted average exercise price (in USD per share)	$ 17.51
Options exercisable, shares	102,750
Options exercisable, weighted average exercise price (in USD per share)	$ 17.51
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	124,667
Options outstanding, weighted average remaining contractual life (in years)	4 years 11 months 5 days
Options outstanding, weighted average exercise price (in USD per share)	$ 19.60
Options exercisable, shares	111,167
Options exercisable, weighted average exercise price (in USD per share)	$ 19.71
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	57,500
Options outstanding, weighted average remaining contractual life (in years)	9 years 0 months 16 days
Options outstanding, weighted average exercise price (in USD per share)	$ 30.05
Options exercisable, shares	15,830
Options exercisable, weighted average exercise price (in USD per share)	$ 30.41
Range of exercise prices, lower limit (in USD per share)	$ 20.49
Range of exercise prices, upper limit (in USD per share)	$ 33.36

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(iii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (g)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(iii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(i)-(ii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(i)-(ii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (e)(1)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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The ceiling 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

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (g)

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