Changes in Carrying Amount of Goodwill (Detail) $ in Thousands	3 Months Ended
Sep. 30, 2019 USD ($)
Goodwill [Line Items]
Balance-beginning of period	$ 319,778
Goodwill acquired	759,239
Foreign currency translation	(448)
Balance-end of period	1,078,569
Compound Semiconductors
Goodwill [Line Items]
Balance-beginning of period	185,721
Foreign currency translation	664
Balance-end of period	186,385
Photonic Solutions
Goodwill [Line Items]
Balance-beginning of period	134,057
Foreign currency translation	(1,112)
Balance-end of period	132,945
Unallocated & Other
Goodwill [Line Items]
Balance-beginning of period	0
Goodwill acquired	759,239
Balance-end of period	$ 759,239

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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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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