v3.8.0.1

Cash, Cash Equivalents and Marketable Securities - Additional Information (Detail)	6 Months Ended
	Dec. 29, 2017 USD ($)
Cash, cash equivalents and marketable securities [Line Items]
(Loss) from sales and maturities of available-for-sale	$ (360,000)
Impairment losses	0
Cash, cash equivalents and marketable securities at financial institutions located in the United States	$ 40,000,000
Minimum
Cash, cash equivalents and marketable securities [Line Items]
Maturities period of marketable securities	3 months
Maximum
Cash, cash equivalents and marketable securities [Line Items]
Maturities period of marketable securities	3 years

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- Definition

Cash, cash equivalents and marketable securities.

+ References

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Cash, cash equivalents and marketable securities

+ References

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- Definition

Marketable Securities Maturity Period

+ References

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- Definition

The amount of other than temporary impairment (OTTI) losses on equity securities, OTTI related to credit losses on debt securities, and OTTI losses on debt securities when the entity intends to sell the securities or it is more likely than not that the entity will be required to sell the securities before recovery of its amortized cost basis. Additionally, this item includes OTTI losses recognized during the period on investments accounted for under the cost method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 8B
-URI http://asc.fasb.org/extlink&oid=82897076&loc=SL6284393-111563

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- Definition

The net realized gains or losses on investments during the period, not including gains or losses on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04.3(a))
-URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 325
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=75031664&loc=d3e22529-158502

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