Financial Instruments, Short-term Investments (Details) - USD ($) $ in Thousands	Jun. 27, 2015	Jun. 28, 2014
Available-for-sale Securities [Abstract]
Amortized Cost Basis	$ 75,022	$ 49,853
Gross Unrealized Gains	132	100
Gross Unrealized Loss	0	0
Estimated Fair Value	75,154	49,953
US Treasury Securities [Member]
Available-for-sale Securities [Abstract]
Amortized Cost Basis	75,022	49,853
Gross Unrealized Gains	132	100
Gross Unrealized Loss	0	0
Estimated Fair Value	$ 75,154	$ 49,953