Related Party Transactions - Additional Information (Detail) - Hitachi Ltd - shares shares in Millions	3 Months Ended
Dec. 26, 2015	Jun. 30, 2018	Jul. 01, 2017
Related Party Transaction [Line Items]
Number of shares sold by Hitachi (shares)	6.6
Percentage of outstanding common stock owned by related party (less than)		5.00%	5.00%

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.

No definition available.

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Balance Type:	na
Period Type:	duration