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Investments, Forward Contracts and Fair Value Measurements - Additional Information (Details) - USD ($) shares in Millions		12 Months Ended
	Oct. 30, 2018	Jun. 29, 2019	Jun. 30, 2018	Jul. 01, 2017
Investments
Total debt available-for-sale securities		$ 600,000	$ 189,600,000
Other-than-temporary impairment charges		0	0	$ 0
Contingent consideration liability, up to		$ 63,000,000.0
Contingent consideration period		4 years
Contingent consideration liability		$ 38,400,000
Change in fair value of contingent liability		5,900,000	0	$ 0
Not designated \| Foreign exchange forward contracts
Investments
Derivative asset, fair value		1,200,000
Derivative liability, fair value		4,000,000.0
Loss on derivatives		$ 6,900,000	800,000
Not designated \| Foreign exchange forward contracts \| Held to purchase
Investments
Derivative term		120 days
Notional amount of forward contracts		$ 117,800,000	167,500,000
Not designated \| Foreign exchange forward contracts \| Held to sell
Investments
Notional amount of forward contracts		31,300,000	28,600,000
Short-term investments
Investments
Deferred compensation plan assets		1,500,000	1,600,000
Short-term investments \| Debt securities
Investments
Deferred compensation plan assets		400,000
Short-term investments \| Money market funds
Investments
Deferred compensation plan assets		300,000
Short-term investments \| Marketable equity securities
Investments
Deferred compensation plan assets		800,000
Cash equivalents
Investments
Total debt available-for-sale securities			21,200,000
Short-term investments
Investments
Total debt available-for-sale securities			167,700,000
Other non-current assets
Investments
Total debt available-for-sale securities		600,000	700,000
Money market funds \| Short-term investments
Investments
Deferred compensation plan assets			300,000
Marketable equity securities \| Short-term investments
Investments
Deferred compensation plan assets			900,000
Debt securities \| Short-term investments
Investments
Deferred compensation plan assets			$ 400,000
RPC Photonics, Inc.
Investments
Contingent consideration liability, up to	$ 53,000,000.0
Contingent consideration period	4 years
Contingent consideration liability	$ 36,200,000	30,300,000
Change in fair value of contingent liability		$ 5,900,000
Lumentum
Investments
Equity securities sold (in shares)				7.2
Gain on sale of investments				$ 203,000,000.0
Tax effect on sale of investments				$ 0