Convertible Senior Notes (Warrants) (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	1 Months Ended
Jun. 30, 2016	Jun. 30, 2012
2017 Warrants
Debt Instrument [Line Items]
Proceeds from sale of warrants		$ 38.4
Settlement of warrants	$ 87.9
Shares exercisable upon conversion		2
Exercise price of warrants (in dollars per share)		$ 34.20
Senior Notes \| Convertible Senior Notes Due 2017
Debt Instrument [Line Items]
Debt, aggregate principal amount repurchased	$ 220.0

Class of Warrant or Right, Strike Price of Warrants or Rights

No definition available.

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- Definition

Shares Exercisable Upon Conversion

+ References

No definition available.

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Face (par) amount of the original debt instrument that was repurchased.

+ References

No definition available.

+ Details

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- Definition

The aggregate amount paid by the entity to reacquire the right to purchase equity shares at a predetermined price, usually issued together with corporate debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financing Activities
-URI http://asc.fasb.org/extlink&oid=6513228

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3291-108585

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- Definition

The cash inflow associated with the amount received from holders exercising their stock warrants.

+ References

No definition available.

+ Details

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- Details

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