Financial Instruments (Narrative) (Detail) $ in Thousands	12 Months Ended
Jun. 30, 2018 USD ($) Customer Product	Jun. 30, 2017 USD ($) Customer Product	Jun. 30, 2016 Customer Product
Accounts Receivable
Financial Instruments Owned and Pledged as Collateral [Line Items]
Concentration Risk, Number \| Customer	3	3
Accounts Receivable \| Customer One
Financial Instruments Owned and Pledged as Collateral [Line Items]
Percentage of net trade accounts receivable attributable to single customer	28.00%	32.00%
Accounts Receivable \| Customer Two
Financial Instruments Owned and Pledged as Collateral [Line Items]
Percentage of net trade accounts receivable attributable to single customer	19.00%	20.00%
Accounts Receivable \| Customer three
Financial Instruments Owned and Pledged as Collateral [Line Items]
Percentage of net trade accounts receivable attributable to single customer	13.00%	15.00%
Net sales \| Customer One
Financial Instruments Owned and Pledged as Collateral [Line Items]
Concentration Risk, Number \| Customer	1	1	1
Percentage of net sales attributable to single customer	16.00%	12.00%	14.00%
Net sales \| Customer Two
Financial Instruments Owned and Pledged as Collateral [Line Items]
Percentage of net sales attributable to single customer	11.00%	11.00%	7.00%
Product Concentration \| Net sales
Financial Instruments Owned and Pledged as Collateral [Line Items]
Concentration Risk, Number \| Product	0	0	0
Minimum percentage of net sales for separate disclosure	10.00%	10.00%	10.00%
Geographic Concentration \| Purchases \| Europe
Financial Instruments Owned and Pledged as Collateral [Line Items]
Percentage of purchases for a single geographic area	15.00%	17.00%	22.00%
Net assets by geographic area \| $	$ 68,149	$ 68,235
Geographic Concentration \| Purchases \| Asia
Financial Instruments Owned and Pledged as Collateral [Line Items]
Percentage of purchases for a single geographic area	61.00%	62.00%	56.00%
Net assets by geographic area \| $	$ 36,633	$ 50,641

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- Definition

Minimum Percentage of Net Sales for Separate Disclosure

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Represents percentage of net sales attributable to a single customer.

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- Definition

Carrying amount of total assets less total liabilities of a designated geographic area if disclosed as a concentration risk.

+ References

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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