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v3.21.2

Acquisitions - Narrative (Details) $ in Thousands | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Jun. 27, 2021 USD ($) | Jun. 28, 2020 USD ($) | Jun. 27, 2021 USD ($) acquisition | Sep. 27, 2020 USD ($) acquisition | Jun. 28, 2020 USD ($) | Jul. 26, 2021 employee
Business Acquisition [Line Items] |  |  |  |  |  |
Contingent earn-out liability | $ 31,200 |  | $ 31,200 |  |  |
Gain on fair value adjustment to contingent consideration | (30) | $ (50) | $ 163 |  | $ 1,521 |
Minimum |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Significant unobservable input, earn-out period |  |  | 2 years |  |  |
Minimum | Existing customer contracts |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Useful life of intangible assets |  |  | 1 year |  |  |
Minimum | Trade names |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Useful life of intangible assets |  |  | 3 years |  |  |
Maximum |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Significant unobservable input, earn-out period |  |  | 3 years |  |  |
Maximum | Existing customer contracts |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Useful life of intangible assets |  |  | 10 years |  |  |
Maximum | Trade names |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Useful life of intangible assets |  |  | 5 years |  |  |
Series of individually immaterial business acquisitions |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Number of acquisitions | acquisition |  |  | 3 |  |  |
Fair value of acquisition purchase price |  |  | $ 29,100 |  |  |
Initial cash payments |  |  | 18,900 |  |  |
Contingent earn-out liability | 10,200 |  | 10,200 |  |  |
Aggregate maximum of contingent consideration | 19,000 |  | $ 19,000 |  |  |
Series of individually immaterial business acquisitions | Minimum |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Earn-out period |  |  | 3 years |  |  |
Series of individually immaterial business acquisitions | Maximum |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Earn-out period |  |  | 4 years |  |  |
SEG and BWF |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Number of acquisitions | acquisition |  |  |  | 2 |  |
Fair value of acquisition purchase price |  |  |  | $ 88,600 |  |
Initial cash payments |  |  |  | 71,400 |  |
Contingent earn-out liability |  |  |  | 16,500 |  |
Aggregate maximum of contingent consideration |  |  |  | $ 28,000 |  |
Earn-out period |  |  |  | 3 years |  |
Payables related to estimated post-closing adjustments |  |  |  | $ 700 |  |
All acquisitions |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Aggregate maximum of contingent consideration | $ 68,200 |  | $ 68,200 |  |  |
Hoare Lea | Subsequent Event |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Number of employees (more than) | employee |  |  |  |  |  | 900

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