Income Taxes (Narrative) (Details) (USD $)	3 Months Ended			6 Months Ended			3 Months Ended		3 Months Ended
	Mar. 29, 2014	Mar. 30, 2013	Sep. 30, 2012	Mar. 29, 2014	Mar. 30, 2013	Sep. 30, 2013	Mar. 30, 2013 Servigistics, Inc	Dec. 29, 2012 Servigistics, Inc	Mar. 29, 2014 ThingWorx, Inc. [Member]
Income Tax Disclosure [Line Items]
Effective income tax rate	10.00%	12.00%		18.00%	(68.00%)
Income before income taxes	$ 48,521,000	$ 19,377,000		$ 101,638,000	$ 31,431,000
Statutory federal income tax rate				35.00%
Tax Benefit Related To Research And Development		2,700,000
Effective Income Tax Rate Reconciliation, Tax Settlement, Foreign, Amount		3,200,000
Non-cash charge to establish a valuation allowance against U.S. deferred tax assets			124,500,000
Finite-lived Intangible Assets Acquired									32,100,000
Identifiable intangible assets								118,300,000
Deferred Tax Liabilities, Intangible Assets									(8,934,000)
Deferred tax assets and liabilities, net								(35,600,000)
Tax benefit recorded to decrease valuation allowance in conjunction with business combination							32,600,000		(8,900,000)
Unrecognized tax benefits	14,700,000			14,700,000		13,700,000
Income tax provision upon recognition of unrecognized tax benefit	13,700,000			13,700,000
Unrecognized tax benefits that would impact valuation allowance	7,300,000			7,300,000
Potentail reduction in unrecognized tax benefits and accrued interest over next 12 months	2,000,000			2,000,000
Adjustments to additional paid in capital, income tax benefit from share-based compensation	$ 1,300,000			$ 8,100,000