Long-Term Equity Compensation (Summary of Options Outstanding and Exercisable) (Details) (USD $)	12 Months Ended
Dec. 31, 2014
$15.30 - 20.00 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of Exercise Prices, minimum	$ 15.30
Range of Exercise Prices, maximum	$ 20.00
Options Outstanding, Number of Options	139,100
Options Outstanding, Weighted Average Remaining Contractual Life (Years)	1 year 6 months 4 days
Options Outstanding, Weighted Average Exercise Price	$ 15.41
Options Exercisable, Number of Options	139,100
Options Exercisable, Weighted Average Exercise Price	$ 15.41
$20.01 - 25.00 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of Exercise Prices, minimum	$ 20.01
Range of Exercise Prices, maximum	$ 25.00
Options Outstanding, Number of Options	555,738
Options Outstanding, Weighted Average Remaining Contractual Life (Years)	2 years 2 months 5 days
Options Outstanding, Weighted Average Exercise Price	$ 23.09
Options Exercisable, Number of Options	555,738
Options Exercisable, Weighted Average Exercise Price	$ 23.09
$25.01 - 30.00 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of Exercise Prices, minimum	$ 25.01
Range of Exercise Prices, maximum	$ 30.00
Options Outstanding, Number of Options	136,892
Options Outstanding, Weighted Average Remaining Contractual Life (Years)	2 years 10 months 17 days
Options Outstanding, Weighted Average Exercise Price	$ 28.14
Options Exercisable, Number of Options	135,955
Options Exercisable, Weighted Average Exercise Price	$ 28.14
$30.01 - 40.00 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of Exercise Prices, minimum	$ 30.01
Range of Exercise Prices, maximum	$ 40.00
Options Outstanding, Number of Options	519,783
Options Outstanding, Weighted Average Remaining Contractual Life (Years)	2 years 3 months 4 days
Options Outstanding, Weighted Average Exercise Price	$ 31.96
Options Exercisable, Number of Options	513,009
Options Exercisable, Weighted Average Exercise Price	$ 31.96
$40.01 - 50.00 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of Exercise Prices, minimum	$ 40.01
Range of Exercise Prices, maximum	$ 50.00
Options Outstanding, Number of Options	479,685
Options Outstanding, Weighted Average Remaining Contractual Life (Years)	1 year 4 months 13 days
Options Outstanding, Weighted Average Exercise Price	$ 46.58
Options Exercisable, Number of Options	479,685
Options Exercisable, Weighted Average Exercise Price	$ 46.58
$50.01 - 58.07 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of Exercise Prices, minimum	$ 50.01
Range of Exercise Prices, maximum	$ 58.07
Options Outstanding, Number of Options	121,013
Options Outstanding, Weighted Average Remaining Contractual Life (Years)	2 years 4 months 24 days
Options Outstanding, Weighted Average Exercise Price	$ 54.95
Options Exercisable, Number of Options	121,013
Options Exercisable, Weighted Average Exercise Price	$ 54.95
$15.30 - 58.07 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of Exercise Prices, minimum	$ 15.30
Range of Exercise Prices, maximum	$ 58.07
Options Outstanding, Number of Options	1,952,211
Options Outstanding, Weighted Average Remaining Contractual Life (Years)	2 years 7 days
Options Outstanding, Weighted Average Exercise Price	$ 33.01
Options Exercisable, Number of Options	1,944,500
Options Exercisable, Weighted Average Exercise Price	$ 33.01

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

+ 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)(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)

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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

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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