Financial Information of Company's Operation by Segment (Detail) - USD ($) $ in Thousands	3 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Jun. 30, 2019
Segment Reporting Reconciling Item For Operating Profit Loss From Segment To Consolidated [Line Items]
Revenues	$ 340,409	$ 314,433
Operating income (loss)	(18,475)	37,213
Interest expense	(6,968)	(5,584)
Other income (expense), net	(5,079)	713
Income Taxes	(4,524)	6,193
Net earnings (loss)	(25,998)	26,149
Depreciation and amortization	26,948	22,170
Expenditures for property, plant & equipment	25,636	34,918
Segment assets	5,370,686		$ 1,953,773
Goodwill	1,078,569		319,778
Income taxes	4,524	(6,193)
Photonic Solutions
Segment Reporting Reconciling Item For Operating Profit Loss From Segment To Consolidated [Line Items]
Revenues	141,357	135,156
Inter-segment revenues	2,650	2,896
Operating income (loss)	13,024	15,912
Depreciation and amortization	6,816	6,199
Expenditures for property, plant & equipment	9,389	12,051
Segment assets	685,064
Goodwill	132,945		134,057
Compound Semiconductors
Segment Reporting Reconciling Item For Operating Profit Loss From Segment To Consolidated [Line Items]
Revenues	177,001	179,277
Inter-segment revenues	13,933	19,215
Operating income (loss)	26,521	21,301
Depreciation and amortization	16,389	15,971
Expenditures for property, plant & equipment	13,483	22,867
Segment assets	1,335,595
Goodwill	186,385		185,721
Unallocated & Other
Segment Reporting Reconciling Item For Operating Profit Loss From Segment To Consolidated [Line Items]
Revenues	22,051
Inter-segment revenues	(16,583)	$ (22,111)
Operating income (loss)	(58,019)
Depreciation and amortization	3,743
Expenditures for property, plant & equipment	2,764
Segment assets	3,350,027
Goodwill	$ 759,239		$ 0