Acquisitions (Unaudited Pro-Forma Consolidated Results Of Operations) (Details) (Aegis Lightwave, Inc. [Member], USD $) In Thousands, except Per Share data	3 Months Ended
Sep. 30, 2011	Sep. 30, 2010
Aegis Lightwave, Inc. [Member]
Business Acquisition [Line Items]
Net revenues	$ 138,373	$ 127,004
Net earnings attributable to II-VI Incorporated	$ 18,579	$ 18,998
Basic earnings per share	$ 0.30	$ 0.31
Diluted earnings per share	$ 0.29	$ 0.30

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

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