Derivative Instruments and Hedging Activities (Pretax Amounts Recognized In Accumulated Other Comprehensive Income On Currency Contracts) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Mar. 31, 2018	Apr. 01, 2017	Mar. 31, 2018	Apr. 01, 2017
Currency exchange contracts gain (loss)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning unrealized net gain (loss) in AOCI	$ (444)	$ 1,423	$ (443)	$ (400)
Net (gain) loss reclassified into revenue (effective portion)	1,146	(318)	1,304	(737)
Net gain (loss) recognized in OCI (effective portion)	(1,794)	(1,220)	(1,953)	1,022
Ending unrealized net gain (loss) in AOCI	(1,092)	(115)	(1,092)	(115)
Interest rate swaps
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning unrealized net gain (loss) in AOCI	5,027	4,267	3,499	0
Net (gain) loss reclassified into revenue (effective portion)	(220)	416	(239)	416
Net gain (loss) recognized in OCI (effective portion)	2,118	(373)	3,665	3,894
Ending unrealized net gain (loss) in AOCI	$ 6,925	$ 4,310	$ 6,925	$ 4,310

The amount of unrealized net (loss) gain in Accumulated Other Comprehensive Income, pretax.

No definition available.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624171-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4D
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624177-113959

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- Definition

Amount before tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6441202&loc=d3e80720-113993

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=66004124&loc=SL7669646-108580

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=66004124&loc=d3e637-108580

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