Derivative Instruments and Hedging Activities (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended
	Dec. 30, 2017	Dec. 31, 2016	Sep. 30, 2017
Derivative [Line Items]
Gross notional amount of foreign exchange derivatives outstanding	$ 44,890		$ 29,136
Net notional amount of foreign exchange derivatives	39,951		24,093
Recognized in earnings as a result of the ineffectiveness of cash flow hedges (less than $1)	1	$ 1
Gain (loss) projected to be reclassified from Accumulated Other Comprehensive Income into earnings, within twelve months	$ (438)
Maximum remaining maturity of any forward or optional contract derivatives (in years)	2 years 1 month
Cash flow derivatives
Derivative [Line Items]
Foreign currency exchange contract (liability), net value	$ 369		478
Foreign currency exchange contract, net asset market value	151		73
Foreign currency exchange contract, net liability market value	520		551
Interest rate swaps
Derivative [Line Items]
Gain (loss) projected to be reclassified from Accumulated Other Comprehensive Income into earnings, within twelve months	1,359
Notional amount	$ 255,000
Fixed interest rate	1.256%
Interest rate swaps	$ 5,027		3,499
Foreign exchange balance sheet derivative contracts
Derivative [Line Items]
Gross notional amount of foreign exchange derivatives outstanding	48,441		52,208
Net notional amount of foreign exchange derivatives	14,990		14,762
Foreign currency exchange contract (liability), net value	$ (21)		$ 77