v2.3.0.15
Composition Of Certain Financial Statement Captions (Schedule Of Gross Unrealized Losses And The Fair Value For Available-For-Sale Securities) (Details) (USD $)
In Thousands
Sep. 30, 2011
Sep. 24, 2010
Schedule of Available-for-sale Securities [Line Items]  
Fair Value, Less than 12 months$ 171,076$ 92,606
Gross Unrealized Losses, Less than 12 months(543)(29)
Fair Value, 12 months or greater2,081 
Gross Unrealized Losses, 12 months or greater(3) 
Fair Value173,15792,606
Gross Unrealized Losses(546)(29)
Corporate Bonds [Member]
  
Schedule of Available-for-sale Securities [Line Items]  
Fair Value, Less than 12 months87,613 
Gross Unrealized Losses, Less than 12 months(487) 
Fair Value87,613 
Gross Unrealized Losses(487) 
Municipal Debt Securities [Member]
  
Schedule of Available-for-sale Securities [Line Items]  
Fair Value, Less than 12 months79,46662,494
Gross Unrealized Losses, Less than 12 months(52)(25)
Fair Value, 12 months or greater2,081 
Gross Unrealized Losses, 12 months or greater(3) 
Fair Value81,54762,494
Gross Unrealized Losses(55)(25)
U.S. Agency Securities [Member]
  
Schedule of Available-for-sale Securities [Line Items]  
Fair Value, Less than 12 months3,99730,112
Gross Unrealized Losses, Less than 12 months(4)(4)
Fair Value3,99730,112
Gross Unrealized Losses$ (4)$ (4)