Earnings Per Share and Capital Structure Stock Repurchase Plan (Details) (USD $) In Millions, except Share data, unless otherwise specified	0 Months Ended	4 Months Ended	6 Months Ended
Mar. 08, 2013	Jun. 30, 2013	Jun. 30, 2013
Stock Repurchase Program, Authorized Amount	$ 50
Stock Repurchased and Retired During Period, Shares		384,800
Stock Repurchased and Retired During Period, Value		16.1
Stock Repurchase Program, Remaining Authorized Repurchase Amount			$ 33.9

Number of shares that have been repurchased and retired during the period.

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

-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

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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- Definition

Equity impact of the value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital).

+ References

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- Definition

Amount of a stock repurchase plan authorized by an entity's Board of Directors.

+ References

No definition available.

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- Definition

Amount remaining of a stock repurchase plan authorized by an entity's Board of Directors.

+ References

No definition available.

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