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Net Income Per Share (Narrative) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Debt Instrument [Line Items]
Interest expense	$ 4.6	$ 13.3
Maximum percentage of common stock shares for preferred stock conversion	19.99%
Maximum number of common stock shares for preferred stock conversion	0.9
Convertible Debt [Member]
Debt Instrument [Line Items]
Interest expense	$ 3.3	$ 5.0

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- Definition

Amount of the cost of borrowed funds accounted for as interest expense for debt.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.8)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688



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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 8

-Article 5

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Maximum number of common stock shares for preferred stock conversion under NYSE rules prior to obtaining shareholder approval

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Maximum percentage of common stock shares for preferred stock conversion under NYSE rules prior to shareholder approval

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