Earnings Per Share (Schedule Of Computation Of Earnings Per Share) (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
Sep. 30, 2012	Sep. 30, 2011
Earnings Per Share [Line Items]
Net earnings attributable to II-VI Incorporated	$ 12,718	$ 18,579
Weighted average shares	62,786	62,698
Basic earnings attributable to II-VI Incorporated per common share	$ 0.20	$ 0.30
Net earnings attributable to II-VI Incorporated	$ 12,718	$ 18,579
Weighted average shares	62,786	62,698
Dilutive effect of common stock equivalents	1,413	1,367
Diluted weighted average common shares	64,199	64,065
Diluted earnings attributable to II-VI Incorporated per common share	$ 0.20	$ 0.29

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

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+ Details

- Definition

The amount of net income (loss) for 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.

+ References+ Details

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

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-Glossary Net Income

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-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

-Number 51

-Paragraph A7

-Appendix A

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+ Details

- 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.

+ References

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-Glossary Weighted-Average Number of Common Shares Outstanding

-URI http://asc.fasb.org/extlink&oid=6528421

+ Details