Restructuring And Related Costs (Summary Of Severance Charges On Statement Of Income) (Details) - USD ($)	3 Months Ended	12 Months Ended
	Jul. 02, 2016	Oct. 01, 2016	Oct. 03, 2015	Sep. 27, 2014
Restructuring Cost and Reserve [Line Items]
Restructuring expense		$ 2,165,000	$ 0
2016 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring expense	$ 1,237,000	2,165,000
2016 Restructuring Plan [Member] | Cost of Sales [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring expense		1,061,000
2016 Restructuring Plan [Member] | Selling and Marketing Expense [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring expense		284,000
2016 Restructuring Plan [Member] | General and Administrative Expense [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring expense		815,000
2016 Restructuring Plan [Member] | Research and Development Expense [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring expense		5,000
2014 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring expense		0		$ 6,336,000
2014 Restructuring Plan [Member] | Cost of Sales [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring expense				3,507,000
2014 Restructuring Plan [Member] | Selling and Marketing Expense [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring expense				1,805,000
2014 Restructuring Plan [Member] | General and Administrative Expense [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring expense				1,024,000
Test [Member] | 2016 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring expense		847,000
Test [Member] | 2016 Restructuring Plan [Member] | Cost of Sales [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring expense		299,000
Test [Member] | 2016 Restructuring Plan [Member] | Selling and Marketing Expense [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring expense		129,000
Test [Member] | 2016 Restructuring Plan [Member] | General and Administrative Expense [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring expense		414,000
Test [Member] | 2016 Restructuring Plan [Member] | Research and Development Expense [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring expense		5,000
Test [Member] | 2014 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring expense				6,336,000
Test [Member] | 2014 Restructuring Plan [Member] | Cost of Sales [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring expense				3,507,000
Test [Member] | 2014 Restructuring Plan [Member] | Selling and Marketing Expense [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring expense				1,805,000
Test [Member] | 2014 Restructuring Plan [Member] | General and Administrative Expense [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring expense				1,024,000
Sensors [Member] | 2016 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring expense		1,318,000
Sensors [Member] | 2016 Restructuring Plan [Member] | Cost of Sales [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring expense		762,000
Sensors [Member] | 2016 Restructuring Plan [Member] | Selling and Marketing Expense [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring expense		155,000
Sensors [Member] | 2016 Restructuring Plan [Member] | General and Administrative Expense [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring expense		401,000
Sensors [Member] | 2016 Restructuring Plan [Member] | Research and Development Expense [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring expense		$ 0
Sensors [Member] | 2014 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring expense				0
Sensors [Member] | 2014 Restructuring Plan [Member] | Cost of Sales [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring expense				0
Sensors [Member] | 2014 Restructuring Plan [Member] | Selling and Marketing Expense [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring expense				0
Sensors [Member] | 2014 Restructuring Plan [Member] | General and Administrative Expense [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring expense				$ 0