Acquisition - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Jun. 30, 2018
Business Acquisition [Line Items]
Net cash paid at acquisition	$ 45,229	$ 79,465
Goodwill	298,308		$ 270,678
II-VI Photonics Segment
Business Acquisition [Line Items]
Goodwill	133,334		$ 114,398
CoAdna, Inc
Business Acquisition [Line Items]
Net cash paid at acquisition	85,000
Acquisition, net of cash acquired	42,200
Goodwill	24,844
Business acquisition, transaction costs	1,900
Fair value of accounts receivable acquired	5,700
Accounts receivable, gross contractual amount	5,700
Business acquisition, revenue of acquired entity	3,000
CoAdna, Inc | II-VI Photonics Segment
Business Acquisition [Line Items]
Goodwill	$ 24,800