Revenue from Contracts with Customers (Additional Information) (Details) - USD ($) $ in Thousands	3 Months Ended
	Dec. 28, 2019	Sep. 30, 2019
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Contract with Customer, Asset, Reclassified to Receivable	$ 6,800
Contract with Customer, Asset, Additions during Period	6,700
Deferred Revenue, Revenue Recognized	178,200
Deferred Revenue, Additions	147,000
Short Term and Long Term Accounts Receivable	400,800	$ 412,500
Refund Liability	25,900	22,900
Deferred revenue	368,089	396,632
Revenue, Remaining Performance Obligation, Amount	1,077,800
Other Current Assets
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Capitalized Contract Cost, Net	29,800	27,700
Other Assets
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Capitalized Contract Cost, Net	67,300	$ 64,800
Onshape [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Deferred Revenue, Additions	2,700
Unrecorded [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Revenue, Remaining Performance Obligation, Amount	$ 709,700