Borrowings and Credit Arrangements - Convertible Notes and Related Equity Components (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 30, 2013	Sep. 29, 2012
Schedule Of Borrowings [Line Items]
Principal accretion	$ 1,789
2007 Notes [Member]
Schedule Of Borrowings [Line Items]
Notes principal amount	405,000	775,000
Unamortized discount	(15,861)	(50,591)
Net carrying amount	389,139	724,409
Equity component, net of taxes	121,946	233,353
2010 Notes [Member]
Schedule Of Borrowings [Line Items]
Notes principal amount	450,000	450,000
Unamortized discount	(66,314)	(74,062)
Net carrying amount	383,686	375,938
Equity component, net of taxes	60,054	60,054
2012 Notes [Member]
Schedule Of Borrowings [Line Items]
Notes principal amount	500,000	500,000
Unamortized discount	(38,221)	(41,687)
Net carrying amount	461,779	458,313
Equity component, net of taxes	49,195	49,195
2013 Notes [Member]
Schedule Of Borrowings [Line Items]
Notes principal amount	370,000
Principal accretion	1,789
Unamortized discount	(49,171)
Net carrying amount	322,618
Equity component, net of taxes	$ 131,451