Changes in Carrying Amount of Goodwill (Detail) $ in Thousands	9 Months Ended
Mar. 31, 2019 USD ($)
Goodwill [Line Items]
Balance-beginning of period	$ 270,678
Goodwill acquired	49,364
Foreign currency translation	(107)
Balance-end of period	319,935
II-VI Laser Solutions
Goodwill [Line Items]
Balance-beginning of period	98,737
Foreign currency translation	(85)
Balance-end of period	98,652
II-VI Photonics
Goodwill [Line Items]
Balance-beginning of period	109,670
Goodwill acquired	26,015
Foreign currency translation	(22)
Balance-end of period	135,663
II-VI Performance Products
Goodwill [Line Items]
Balance-beginning of period	62,271
Goodwill acquired	23,349
Balance-end of period	$ 85,620

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-SubTopic 20
-Section 45
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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-SubTopic 20
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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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