Financial Instruments (Tables)
 9 Months Ended
Mar. 25, 2017
Derivative Instruments and Hedging Activities Disclosure [Abstract]  
Available-for-sale investments [Table Text Block]
Fair values were as follows:
 
March 25, 2017
 
June 25, 2016
 
Amortized Cost
 
Gross Unrealized Gain
 
Gross Unrealized Loss
 
Estimated Fair Value
 
Amortized Cost
 
Gross Unrealized Gain
 
Gross Unrealized Loss
 
Estimated Fair Value
 
(in thousands)
Available-for-sale investments
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
U.S. Treasury bills
$
500,073

 
$
—

 
$
919

 
$
499,154

 
$
124,950

 
$
489

 
$
—

 
$
125,439

Total available-for-sale investments
$
500,073

 
$
—

 
$
919

 
$
499,154

 
$
124,950

 
$
489

 
$
—

 
$
125,439
Schedule of long-term debt [Table Text Block]
The following table summarizes the Company’s long-term debt:
 
March 25,
2017
 
June 25,
2016
 
(in thousands)
2.5% fixed rate notes due November 2018
$
500,000

 
$
500,000

3.375% fixed rate notes due March 2023
500,000

 
500,000

Short-term credit agreement
—

 
250,000

Total
1,000,000

 
1,250,000

Less: Current portion
—

 
(249,717
)
Less: Reduction for unamortized discount and debt issuance costs
(8,123
)
 
(10,193
)
Total long-term debt
$
991,877

 
$
990,090