Investments and Fair Value Measurements (Details 3) (USD $) In Millions, unless otherwise specified	3 Months Ended		12 Months Ended
	Sep. 27, 2014		Jun. 28, 2014
Maximum
Foreign Currency Forward Contracts
Foreign currency forward contracts, expiration period	120 days		120 days
Recurring basis
Fair Value Measurements
Total debt available-for-sale securities	$ 575.1
Money market funds	197.0
Trading securities	3.9
Total assets	776.0	[1]
Recurring basis | Cash and cash equivalents
Fair Value Measurements
Total assets	202.0	[1]
Recurring basis | Short-term investments
Fair Value Measurements
Total assets	537.7	[1]
Recurring basis | Restricted cash
Fair Value Measurements
Total assets	31.7	[1]
Recurring basis | Other non-current assets
Fair Value Measurements
Total assets	4.6	[1]
Recurring basis | U.S. treasuries
Fair Value Measurements
Total debt available-for-sale securities	27.5
Recurring basis | U.S. agencies
Fair Value Measurements
Total debt available-for-sale securities	87.9
Recurring basis | Municipal bonds and sovereign debt instruments
Fair Value Measurements
Total debt available-for-sale securities	15.4
Recurring basis | Asset-backed securities
Fair Value Measurements
Total debt available-for-sale securities	87.1
Recurring basis | Corporate securities
Fair Value Measurements
Total debt available-for-sale securities	357.2
Recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value Measurements
Total debt available-for-sale securities	27.5
Money market funds	197.0
Trading securities	3.9
Total assets	228.4	[1]
Recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1) | U.S. treasuries
Fair Value Measurements
Total debt available-for-sale securities	27.5
Recurring basis | Significant Other Observable Inputs (Level 2)
Fair Value Measurements
Total debt available-for-sale securities	547.6
Total assets	547.6	[1]
Recurring basis | Significant Other Observable Inputs (Level 2) | U.S. agencies
Fair Value Measurements
Total debt available-for-sale securities	87.9
Recurring basis | Significant Other Observable Inputs (Level 2) | Municipal bonds and sovereign debt instruments
Fair Value Measurements
Total debt available-for-sale securities	15.4
Recurring basis | Significant Other Observable Inputs (Level 2) | Asset-backed securities
Fair Value Measurements
Total debt available-for-sale securities	87.1
Recurring basis | Significant Other Observable Inputs (Level 2) | Corporate securities
Fair Value Measurements
Total debt available-for-sale securities	$ 357.2

[1] $202.0 million in cash and cash equivalents, $537.7 million in short-term investments, $31.7 million in restricted cash, and $4.6 million in other non-current assets on the Company's Consolidated Balance Sheet.