Stock-Based Compensation Stock Options by Range of Exercise Prices (Details) (USD $)	12 Months Ended
Dec. 31, 2014
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, End of Period [Abstract]
Options Outstanding	7,847,338
Weighted Average Exercise Price	$ 18.34
Remaining Life (Years)	5 years 9 months
Options Exercisable	5,076,676
Weighted Average Exercise Price	$ 19.96
Range Of Exercise Prices One [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, End of Period [Abstract]
Options Outstanding	4,206,026
Weighted Average Exercise Price	$ 13.46
Remaining Life (Years)	6 years 10 months
Options Exercisable	2,767,037
Weighted Average Exercise Price	$ 13.46
Range Of Exercise Prices Two [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, End of Period [Abstract]
Options Outstanding	1,856,041
Weighted Average Exercise Price	$ 17.45
Remaining Life (Years)	7 years 7 months
Options Exercisable	524,368
Weighted Average Exercise Price	$ 17.48
Range Of Exercise Prices Three [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, End of Period [Abstract]
Options Outstanding	523,476
Weighted Average Exercise Price	$ 24.89
Remaining Life (Years)	2 years 9 months
Options Exercisable	523,476
Weighted Average Exercise Price	$ 24.89
Range Of Exercise Prices Four [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, End of Period [Abstract]
Options Outstanding	10,500
Weighted Average Exercise Price	$ 27.72
Remaining Life (Years)	2 years 6 months
Options Exercisable	10,500
Weighted Average Exercise Price	$ 27.72
Range Of Exercise Prices Five [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, End of Period [Abstract]
Options Outstanding	1,251,295
Weighted Average Exercise Price	$ 33.24
Remaining Life (Years)	1 year 0 months
Options Exercisable	1,251,295
Weighted Average Exercise Price	$ 33.24

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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 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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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

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-SubTopic 10

-Section 50

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