BALANCE SHEET COMPONENTS - Property and Equipment, Net (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Jun. 30, 2017
Property, Plant and Equipment [Line Items]
Property and Equipment, Gross	$ 41,557	$ 34,708
Less: Accumulated depreciation	(26,766)	(21,792)
Property and Equipment, Net	14,791	12,916
Testing equipment
Property, Plant and Equipment [Line Items]
Property and Equipment, Gross	8,070	7,587
Computer and other equipment
Property, Plant and Equipment [Line Items]
Property and Equipment, Gross	6,378	5,740
Tooling equipment
Property, Plant and Equipment [Line Items]
Property and Equipment, Gross	9,868	7,828
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and Equipment, Gross	1,855	1,528
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and Equipment, Gross	9,403	6,424
Software
Property, Plant and Equipment [Line Items]
Property and Equipment, Gross	$ 5,983	$ 5,601

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(13))
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