Stock-based Compensation (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Reversal of stock-based compensation, actual forfeitures	$ 253	$ 238
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted (in shares)	133,279	116,990
Weighted-average fair value, per option (in dollars per share)	$ 8.19	$ 7.72
Stock Options [Member] \| Exercise Price Range, Range 1 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of exercise prices, per share, minimum (in dollars per share)	$ 25.43
Range of exercise prices, per share, maximum (in dollars per share)	$ 26.97
Stock Options [Member] \| Exercise Price Range, Range 2 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of exercise prices, per share, minimum (in dollars per share)		$ 19.55
Range of exercise prices, per share, maximum (in dollars per share)		$ 21.57

Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures in Period, Value

No definition available.

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

Weighted average grant-date fair value of non-vested options outstanding.

+ References

No definition available.

+ Details

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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 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

+ Details

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