Segment Information (Revenue And Operating Income) (Details) (USD $)	3 Months Ended				6 Months Ended
	Mar. 31, 2012		Apr. 02, 2011		Mar. 31, 2012		Apr. 02, 2011
Revenue	$ 301,125,000		$ 269,189,000		$ 619,401,000		$ 535,741,000
Operating income	6,903,000		24,226,000		39,408,000		41,336,000
Sales and marketing expenses	(98,248,000)		(81,163,000)		(196,025,000)		(165,684,000)
General and administrative expenses	(31,151,000)		(24,712,000)		(60,723,000)		(48,196,000)
Loss on services customer contract			5,000,000
Software Products Segment [Member]
Revenue	221,653,000		203,156,000		458,616,000		405,066,000
Operating income	128,343,000		125,205,000		280,302,000		251,724,000
Services Segment [Member]
Revenue	79,472,000		66,033,000		160,785,000		130,675,000
Operating income	$ 7,959,000	[1]	$ 4,896,000	[1]	$ 15,854,000	[1]	$ 3,492,000	[1]

[1] In the first quarter of 2011, we made a strategic decision to enter into a contract with a customer in the automotive industry, for which we expected our costs to exceed our revenue by approximately $5 million. Services segment operating income in the first three months of 2011 included immediate recognition of the approximately $5 million estimated loss on this contract.W