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Goodwill and Intangible Assets (Tables) | 12 Months Ended
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Sep. 28, 2025
Goodwill and Intangible Assets Disclosure [Abstract] |
Summary of changes in carrying value of goodwill | The following table summarizes the changes in the carrying value of goodwill by reportable segment (in thousands):
| GSG |  | CIG |  | Total
Balance at October 1, 2023 | $ | 659,942 |  |  | $ | 1,220,302 |  |  | $ | 1,880,244 |
Acquisition activity | 84,865 |  |  | — |  |  | 84,865 |
Translation and other adjustments | 6,010 |  |  | 75,450 |  |  | 81,460 |
Balance at September 29, 2024 | 750,817 |  |  | 1,295,752 |  |  | 2,046,569 |
Acquisition activity | — |  |  | 124,292 |  |  | 124,292 |
Goodwill impairment | (92,416) |  |  | — |  |  | (92,416) |
Classified as held-for-sale | — |  |  | (18,533) |  |  | (18,533) |
Translation and other adjustments | 110 |  |  | (10,148) |  |  | (10,038) |
Balance at September 28, 2025 | $ | 658,511 |  |  | $ | 1,391,363 |  |  | $ | 2,049,874 |
Summary of acquired identifiable intangible assets with finite useful lives | The fo llowing tabl e presents the gross amount and accumulated amortization of our acquired identifiable intangible assets with finite useful lives included in "Intangible assets, net" on the consolidated balance sheets ($ in thousands):
| Fiscal Year Ended |  |
| September 28, 2025 |  | September 29, 2024
| Weighted- Average Remaining Life (in years) |  | Gross Amount |  | Accumulated Amortization |  | Net Amount |  | Gross Amount |  | Accumulated Amortization |  | Net Amount
Client relations | 7.3 |  | $ | 169,807 |  |  | $ | (56,241) |  |  | $ | 113,566 |  |  | $ | 198,726 |  |  | $ | (57,975) |  |  | $ | 140,751 |
Backlog | 1.0 |  | 43,919 |  |  | (40,397) |  |  | 3,522 |  |  | 75,194 |  |  | (71,101) |  |  | 4,093 |
Trade names | 0.5 |  | 34,805 |  |  | (30,733) |  |  | 4,072 |  |  | 40,926 |  |  | (25,185) |  |  | 15,741 |
Total |  |  | $ | 248,531 |  |  | $ | (127,371) |  |  | $ | 121,160 |  |  | $ | 314,846 |  |  | $ | (154,261) |  |  | $ | 160,585 |
Summary of estimated amortization expense for the succeeding five years and beyond | Estimated amortization expense for the succeeding five fiscal years and beyond is as follows (in thousands):
| Amount
2026 | $ | 26,546 |
2027 | 17,398 |
2028 | 16,636 |
2029 | 15,722 |
2030 | 11,571 |
Beyond | 33,287 |
Total | $ | 121,160 |

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- Definition Tabular disclosure of the characteristics, including gross value, accumulated amortization amount, weighted average useful life, of finite-lived intangible assets acquired during the period by major class. A major class is composed of intangible assets that can be grouped together because they are similar, either by nature or by their use in the operations of the company. + References No definition available. + Details
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- Definition Tabular disclosure of goodwill by reportable segment and in total which includes a rollforward schedule. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 350 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 24 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482548/350-20-55-24 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 350 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482573/350-20-50-1 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 350 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (h) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482573/350-20-50-1 Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 350 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482573/350-20-50-1 Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 350 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482573/350-20-50-1 Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 350 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482573/350-20-50-1 Reference 7: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 350 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482573/350-20-50-1 Reference 8: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 350 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (e) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482573/350-20-50-1 Reference 9: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 350 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (f) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482573/350-20-50-1 Reference 10: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 350 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (g) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482573/350-20-50-1 Reference 11: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 350 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1A -Publisher FASB -URI https://asc.fasb.org/1943274/2147482573/350-20-50-1A Reference 12: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 350 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482573/350-20-50-2 + Details
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