Stock-Based Compensation (Details 6) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2014
Deferred Compensation Plan
Decrease in rabbi trust deferred compensation liability	$ 4.3
Deferred Performance Shares
Deferred Compensation Plan
Number of common stock deferred into the rabbi trust (in shares)	534,174
Number of shares sold	0

Number of shares of common stock held in a trust that has been set up specifically to accumulate stock for the sole purpose of distribution to participating employees. Shares have been earned but not distributed.

No definition available.

+ Details

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Period Type:	instant

- Details

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- Definition

The amount of the cost recognized during the period for defined contribution plans.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 70

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6414718&loc=d3e28014-114942

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- Definition

Number of share instruments newly issued under a share-based compensation plan.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

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

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