Derivative Instruments and Hedging Activities (Pretax Amounts Recognized In Accumulated Other Comprehensive Income On Currency Contracts) (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 29, 2018	Sep. 30, 2017
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at the beginning of the year	$ 428,777	$ 405,260
Balance at the end of the year	477,932	428,777
Accumulated Foreign Currency Adjustment Attributable to Parent [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at the beginning of the year	3,946	673
Balance at the end of the year	1,772	3,946
Accumulated Foreign Currency Adjustment Attributable to Parent [Member] | Foreign Exchange Cash Flow Hedges [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at the beginning of the year	(443)	(400)
Net (gain) loss reclassified into revenue (effective portion)	399	(459)
Net gain (loss) recognized in OCI (effective portion)	716	416
Balance at the end of the year	672	(443)
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at the beginning of the year	1,953	(255)
Balance at the end of the year	6,320	1,953
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member] | Interest Rate Swap [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at the beginning of the year	3,499	0
Net (gain) loss reclassified into revenue (effective portion)	(1,204)	614
Net gain (loss) recognized in OCI (effective portion)	5,116	2,885
Balance at the end of the year	$ 7,411	$ 3,499