Earnings Per Share (Narrative) (Details) (Convertible Senior Notes 2032 [Member], USD $)	3 Months Ended
Mar. 31, 2014	Mar. 31, 2013
Convertible Senior Notes 2032 [Member]
Debt Instrument [Line Items]
Per share conversion price	$ 25.02	$ 25.02
Convertible debt stock price trigger	$ 32.53	$ 32.53
Incremental common shares attributable to dilutive effect of conversion of debt securities	0	0

The price per share of the conversion feature embedded in the debt instrument.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 470

-SubTopic 20

-Section 50

-Paragraph 5

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6928298&loc=SL6031898-161870

+ Details

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- Definition

Price of the entity's common stock which would be required to be attained for the conversion feature embedded in the debt instrument to become effective.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
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Period Type:	duration

- Details

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- Definition

Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of convertible debt securities using the if-converted method.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 260

-SubTopic 10

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 260

-SubTopic 10

-Section 45

-Paragraph 40

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=7655603&loc=d3e1930-109256

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