Investments and Fair Value Measurements (Details 4) - USD ($) $ in Millions	12 Months Ended
Jul. 02, 2016	Jun. 27, 2015
Maximum
Foreign Currency Forward Contracts
Foreign currency forward contracts, expiration period	120 days	120 days
Recurring basis \| Total fair value
Fair Value Measurements
Total debt available-for-sale securities	$ 347.8	$ 496.4
Marketable equity securities	171.3
Money market funds	274.4	220.6
Trading securities	2.4	3.0
Total assets	795.9	720.0
Recurring basis \| Cash and cash equivalents
Fair Value Measurements
Total assets	295.4	225.4
Recurring basis \| Short-term investments
Fair Value Measurements
Total assets	484.7	464.9
Recurring basis \| Restricted cash
Fair Value Measurements
Total assets	11.3	25.1
Recurring basis \| Other non-current assets
Fair Value Measurements
Total assets	4.5	4.6
Recurring basis \| U.S. treasuries \| Total fair value
Fair Value Measurements
Total debt available-for-sale securities	46.1	51.9
Recurring basis \| U.S. agencies \| Total fair value
Fair Value Measurements
Total debt available-for-sale securities	24.9	96.0
Recurring basis \| Municipal bonds and sovereign debt instruments \| Total fair value
Fair Value Measurements
Total debt available-for-sale securities	2.0	4.0
Recurring basis \| Asset-backed securities \| Total fair value
Fair Value Measurements
Total debt available-for-sale securities	50.2	70.4
Recurring basis \| Corporate securities \| Total fair value
Fair Value Measurements
Total debt available-for-sale securities	224.6	274.1
Recurring basis \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value Measurements
Total debt available-for-sale securities	46.1	51.9
Marketable equity securities	171.3
Money market funds	274.4	220.6
Trading securities	2.4	3.0
Total assets	494.2	275.5
Recurring basis \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| U.S. treasuries
Fair Value Measurements
Total debt available-for-sale securities	46.1	51.9
Recurring basis \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| U.S. agencies
Fair Value Measurements
Total debt available-for-sale securities	0.0	0.0
Recurring basis \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| Municipal bonds and sovereign debt instruments
Fair Value Measurements
Total debt available-for-sale securities	0.0	0.0
Recurring basis \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| Asset-backed securities
Fair Value Measurements
Total debt available-for-sale securities		0.0
Recurring basis \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| Corporate securities
Fair Value Measurements
Total debt available-for-sale securities	0.0	0.0
Recurring basis \| Significant Other Observable Inputs (Level 2)
Fair Value Measurements
Total debt available-for-sale securities	301.7	444.5
Marketable equity securities	0.0
Money market funds	0.0	0.0
Trading securities	0.0	0.0
Total assets	301.7	444.5
Recurring basis \| Significant Other Observable Inputs (Level 2) \| U.S. treasuries
Fair Value Measurements
Total debt available-for-sale securities	0.0	0.0
Recurring basis \| Significant Other Observable Inputs (Level 2) \| U.S. agencies
Fair Value Measurements
Total debt available-for-sale securities	24.9	96.0
Recurring basis \| Significant Other Observable Inputs (Level 2) \| Municipal bonds and sovereign debt instruments
Fair Value Measurements
Total debt available-for-sale securities	2.0	4.0
Recurring basis \| Significant Other Observable Inputs (Level 2) \| Asset-backed securities
Fair Value Measurements
Total debt available-for-sale securities	50.2	70.4
Recurring basis \| Significant Other Observable Inputs (Level 2) \| Corporate securities
Fair Value Measurements
Total debt available-for-sale securities	$ 224.6	$ 274.1

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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