Financial Instruments, Short-term Investments (Details) - USD ($) $ in Thousands	Dec. 29, 2018	Jun. 30, 2018
Debt Securities, Available-for-sale [Abstract]
Estimated Fair Value		$ 1,082,915
Debt Securities, Available-for-sale, Amortized Cost	$ 555,594	1,086,585
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	1	49
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	1,694	3,719
Debt Securities, Available-for-sale	553,901
Certificates of deposit
Debt Securities, Available-for-sale [Abstract]
Debt Securities, Available-for-sale, Amortized Cost	34,997	52,429
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	0	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	0	1
Debt Securities, Available-for-sale	34,997	52,428
Commercial paper
Debt Securities, Available-for-sale [Abstract]
Debt Securities, Available-for-sale, Amortized Cost	38,437	64,354
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax		0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax		0
Debt Securities, Available-for-sale	38,437	64,354
Corporate debt securities
Debt Securities, Available-for-sale [Abstract]
Debt Securities, Available-for-sale, Amortized Cost	264,880	369,734
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	0	39
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	1,318	2,008
Debt Securities, Available-for-sale	263,562	367,765
U.S. Treasury securities
Debt Securities, Available-for-sale [Abstract]
Debt Securities, Available-for-sale, Amortized Cost	217,280	600,068
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	1	10
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	376	1,710
Debt Securities, Available-for-sale	$ 216,905	$ 598,368

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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-Section 50
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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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-Section 45
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