Equity and Share-Based Compensation (Details)	3 Months Ended
Mar. 31, 2015
Common Stock
Changes in number of outstanding shares
Share count at the beginning of the period (in shares)	70,491,732
Grants of restricted stock (in shares)	2,459,754
Forfeitures of restricted stock (in shares)	(511,079)
Share count at the end of the period (in shares)	72,440,407
Treasury Stock
Changes in number of outstanding shares
Share count at the beginning of the period (in shares)	(534,677)
Acquisition of treasury stock (in shares)	(254,881)
Share count at the end of the period (in shares)	(789,558)

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Number of shares of stock issued as of the balance sheet date, including shares that had been issued and were previously outstanding but which are now held in the treasury.

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- Definition

Number of shares related to Restricted Stock Award forfeited during the period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

-Article 5

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Total number of shares issued during the period, including shares forfeited, as a result of Restricted Stock Awards.

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Number of shares that have been repurchased during the period and are being held in treasury.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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

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-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

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-Name Regulation S-X (SX)

-Number 210

-Section 02

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