Goodwill and Intangible Assets - Goodwill (Details) $ in Thousands	9 Months Ended
Jun. 27, 2021 USD ($)
Goodwill
Balance at beginning of the period	$ 993,498
Acquisition activity	18,566
Translation	39,732
Balance at end of the period	1,051,796
GSG
Goodwill
Balance at beginning of the period	516,315
Acquisition activity	14,891
Translation	10,099
Balance at end of the period	541,305
CIG
Goodwill
Balance at beginning of the period	477,183
Acquisition activity	3,675
Translation	29,633
Balance at end of the period	$ 510,491

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
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-Subparagraph (SX 210.9-03(10)(1))
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
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Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 852
-SubTopic 10
-Section 55
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- Definition

Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

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- Definition

Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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

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