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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 No definition available. + Details
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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 + Details
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- Definition 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. + References No definition available. + Details
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