Severance Costs (Details) (USD $)	12 Months Ended
	Oct. 01, 2011	Oct. 02, 2010	Oct. 03, 2009
Severance and Other Postemployment Costs [Line Items]
Severance costs		$ 1,624,000	$ 12,085,000
Severance liability to be paid over the next twelve months	600,000
Severance liability	2,000,000
Cost of Sales [Member]
Severance and Other Postemployment Costs [Line Items]
Severance costs		1,391,000	6,770,000
Selling and Marketing Expense [Member]
Severance and Other Postemployment Costs [Line Items]
Severance costs		100,000	3,989,000
General and Administrative Expense [Member]
Severance and Other Postemployment Costs [Line Items]
Severance costs		133,000	1,171,000
Research and Development Expense [Member]
Severance and Other Postemployment Costs [Line Items]
Severance costs		0	155,000
Test [Member]
Severance and Other Postemployment Costs [Line Items]
Severance costs		1,600,000	10,900,000
Sensors [Member]
Severance and Other Postemployment Costs [Line Items]
Severance costs			$ 1,200,000