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Organization and Summary of Significant Accounting Policies - Investments in Available-for-Sale Securities and Cash Equivalents (Detail) - USD ($) $ in Millions	Jun. 30, 2018	Jun. 24, 2017
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 275.2	$ 361.7
Gross Unrealized Gains	1.5	1.5
Fair Value	276.7	363.2
Money Market [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	275.2	361.7
Fair Value	275.2	361.7
Non-Current Assets [Member] | Auction Rate Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Gross Unrealized Gains	1.5	1.5
Fair Value	$ 1.5	$ 1.5

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- Definition

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

+ References

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- Definition

Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563

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This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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