Earnings Per Common Share (Computation Of Basic And Diluted Earnings Per Common Share) (Details) (USD $) In Millions, except Per Share data	3 Months Ended
Sep. 30, 2011	Sep. 30, 2010
Earnings Per Common Share [Abstract]
Net income attributable to Carpenter	$ 23.8	$ 7.6
Less: earnings and dividends allocated to participating securities	(0.2)	(0.1)
Earnings available for Carpenter common shareholders	$ 23.6	$ 7.5
Weighted average number of common shares outstanding, basic	44.3	44.1
Effect of shares issuable under share based compensation plans	0.8	0.4
Weighted average number of common shares outstanding, diluted	45.1	44.5
Basic earnings per common share	$ 0.53	$ 0.17
Diluted earnings per common share	$ 0.53	$ 0.17

The amount of net income (loss) from continuing operations per each share of common stock or unit outstanding during the reporting period.

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- Definition

The amount of net income (loss) derived from continuing operations during the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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- Definition

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.

+ References+ Details

- Definition

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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-Glossary Weighted-Average Number of Common Shares Outstanding

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