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Balance Sheet Components (Allowance for Product Returns) (Details) - Allowance for Product Returns [Member] - USD ($) $ in Thousands | 12 Months Ended
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Jun. 30, 2018 | Jun. 30, 2017 | Jun. 30, 2016
Valuation And Qualifying Accounts Disclosure [Line Items] |  |  |
Balance at beginning of period | $ 7,296 | $ 3,123 | $ 8,201
Additions | 38,103 | 31,034 | 23,153
Deductions | (34,133) | (26,861) | (28,231)
Balance at end of period | $ 11,266 | $ 7,296 | $ 3,123

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