Borrowing Arrangements (Narrative) (Details) (USD $)	9 Months Ended
	Jun. 29, 2012	Sep. 30, 2011	Mar. 02, 2007 tranches
Debt Instrument [Line Items]
Principal amount of convertible subordinated notes issued	$ 0	$ 26,677,000	$ 200,000,000
Debt Offering Number of Tranches			2
Extinguishment of Debt, Amount	26,700,000
Convertible debt Premium Paid Upon Retirement	21,400,000
Convertible Subordinated Notes 1.25% due March 2010 [Member]
Debt Instrument [Line Items]
Principal amount of convertible subordinated notes issued			100,000,000
Percentage of convertible subordinated notes			1.25%
Convertible Subordinated Notes 1.50% Due March 2012 [Member]
Debt Instrument [Line Items]
Principal amount of convertible subordinated notes issued			$ 100,000,000
Percentage of convertible subordinated notes			1.50%