Stock-Based Compensation (Stock Options by Exercise Price Range) (Details) (USD $)	12 Months Ended
Dec. 31, 2014
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options outstanding, shares	432,269
Options outstanding, weighted average remaining contractual life	4 years 10 months 21 days
Options outstanding, weighted average exercise price	$ 17.55
Options exercisable, shares	340,435
Options exercisable, weighted average exercise price	$ 15.34
Range of Exercise Prices: $0.01 - 9.43
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options outstanding, shares	71,352
Options outstanding, weighted average remaining contractual life	1 year 11 months 19 days
Options outstanding, weighted average exercise price	$ 8.72
Options exercisable, shares	71,352
Options exercisable, weighted average exercise price	$ 8.72
Range of exercise prices, lower limit	$ 0.01
Range of exercise prices, upper limit	$ 9.43
Range of Exercise Prices: $9.44 - 15.60
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options outstanding, shares	70,000
Options outstanding, weighted average remaining contractual life	4 years 22 days
Options outstanding, weighted average exercise price	$ 12.51
Options exercisable, shares	64,166
Options exercisable, weighted average exercise price	$ 12.30
Range of exercise prices, lower limit	$ 9.44
Range of exercise prices, upper limit	$ 15.60
Range of Exercise Prices: $15.61 - 18.75
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options outstanding, shares	146,917
Options outstanding, weighted average remaining contractual life	5 years 7 months 6 days
Options outstanding, weighted average exercise price	$ 17.81
Options exercisable, shares	119,917
Options exercisable, weighted average exercise price	$ 17.60
Range of exercise prices, lower limit	$ 15.61
Range of exercise prices, upper limit	$ 18.75
Range of Exercise Prices: $18.76 - 33.36
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options outstanding, shares	144,000
Options outstanding, weighted average remaining contractual life	6 years 11 days
Options outstanding, weighted average exercise price	$ 24.12
Options exercisable, shares	85,000
Options exercisable, weighted average exercise price	$ 20.00
Range of exercise prices, lower limit	$ 18.76
Range of exercise prices, upper limit	$ 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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- Definition

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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- Definition

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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- Definition

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)

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

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