Earnings or Loss Per Share (Details) - USD ($) shares in Millions, $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Reconciliation of denominators of basic and diluted earnings per share:
Weighted average shares outstanding, basic	131.4	0.1	131.4	0.1
Dilutive effect of stock options	0.7	0.0	0.6	0.0
Weighted average shares outstanding, diluted	132.1	0.1	132.0	0.1
Other information about earnings per share:
Adjustments to numerator of diluted earnings per share	$ 0.0	$ 0.0	$ 0.0	$ 0.0
Anti-dilutive shares excluded from calculation	0.0	0.0	0.0	0.0

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Antidilution

-URI http://asc.fasb.org/extlink&oid=6505113

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

-Publisher FASB

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-Glossary Diluted Earnings Per Share

-URI http://asc.fasb.org/extlink&oid=6510752

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

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-Name Accounting Standards Codification

-Glossary Contingent Stock Agreement

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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The aggregate value of preferred stock dividends and other adjustments necessary to derive net income apportioned to common stockholders.

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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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