Recent Accounting Pronouncements (Policies)	6 Months Ended
Mar. 29, 2026
Accounting Changes and Error Corrections [Abstract]
Recent Accounting Pronouncements	In September 2025, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update (“ASU”) No. 2025-06, Intangibles - Goodwill and Other - Internal-Use Software (Subtopic 350-40): Targeted Improvements to the Accounting for Internal-Use Software, which clarifies and modernizes the accounting for costs related to internal-use software guidance in subtopic 350-40. The guidance removes all references to project stages throughout Accounting Standards Codification ("ASC") 350-40 and clarifies the threshold entities apply to begin capitalizing costs. The amendments in this ASU are effective for annual periods beginning after December 15, 2027 (fiscal 2029 for us). Early adoption is permitted. We are currently evaluating the impact of this guidance on our consolidated financial statements; however, we do not plan to adopt it before fiscal 2029. In July 2025, the FASB issued ASU No. 2025-05, Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Loss for Accounts Receivable and Contract Assets, which provides a practical expedient (for all entities) and an accounting policy election (for all entities, other than public business entities, that elect the practical expedient) related to the estimation of expected credit losses for current accounts receivable and current contract assets that arise from transactions accounted for under ASC Topic 606, "Revenue from Contracts with Customers". The amendments in this ASU are effective for annual periods beginning after December 15, 2025 (fiscal 2027 for us). Early adoption is permitted. We are currently evaluating the impact of this guidance on our consolidated financial statements; however, we do not plan to adopt it before fiscal 2027. In December 2023, the FASB issued ASU No. 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures, which requires entities to disclose additional income tax information on an annual basis, primarily related to the rate reconciliation and income taxes paid. The amendments in the ASU are intended to enhance the transparency and decision usefulness of income tax disclosures. The amendments in this ASU are effective for annual periods beginning after December 15, 2024 (fiscal 2026 for us). The adoption of this ASU will not have a material impact on our consolidated financial statements. In November 2024, the FASB issued ASU No. 2024-03, Income Statement (Topic 220): Reporting Comprehensive Income. ASU 2024-03 does not change or remove current expense presentation requirements within the consolidated statements of income. However, the amendments require disclosure, on an annual and interim basis, of disaggregated information about certain income statement expense line items within the notes to the consolidated financial statements. The amendments in this update are effective for annual reporting periods beginning after December 15, 2026 (fiscal 2028 for us), and interim reporting periods beginning after December 15, 2027 (first quarter of fiscal 2029 for us). Early adoption is permitted. The adoption of this ASU will not have a material impact on our consolidated financial statements. In November 2024, the FASB issued ASU No. 2024-04, Debt—Debt with Conversion and Other Options (Subtopic 470-20): Induced Conversions of Convertible Debt Instruments, which clarifies the requirements related to accounting for the settlement of a debt instrument as an induced conversion. The amendments in this update are effective for annual reporting periods beginning after December 15, 2025, including interim periods within those fiscal years (first quarter of fiscal 2027 for us). Early adoption is permitted. We are currently evaluating the impact of this guidance on our consolidated financial statements; however, we do not plan to adopt this ASU before fiscal 2027.
Contract Assets and Contract Liabilities and Remaining Unsatisfied Performance Obligation (“RUPO”)	We invoice customers based on the contractual terms of each contract. However, the timing of revenue recognition may differ from the timing of invoice issuance. Contract assets represent revenue recognized in excess of the amounts for which we have the contractual right to bill our customers. Such amounts are recoverable from customers based upon various measures of performance, including achievement of certain milestones or completion of a contract. In addition, many of our time-and-materials arrangements are billed in arrears pursuant to contract terms that are standard within the industry, resulting in contract assets and/or unbilled receivables being recorded, as revenue is recognized in advance of billings. Contract retentions, included in contract assets, represent amounts withheld by clients until certain conditions are met or the project is completed, which may extend beyond one year. Contract liabilities consist of billings in excess of revenue recognized. Contract liabilities decrease as we recognize revenue from the satisfaction of the related performance obligation and increase as billings in advance of revenue recognition occur. Contract assets and liabilities are reported in a net position on a contract-by-contract basis at the end of each reporting period. There were no substantial non-current contract assets for the periods presented.Revenue is recognized by measuring progress over time under Accounting Standards Codification Topic 606, "Revenue from Contracts with Customers". We estimate and measure progress on our contracts over time whereby we compare our total costs incurred on each contract as a percentage of the total expected contract costs. Changes in those estimates could result in the recognition of cumulative catch-up adjustments to the contract’s inception-to-date revenue, costs and profit in the period in which such changes are made. Remaining Unsatisfied Performance Obligation (“RUPO”) Our RUPO represents a measure of the total dollar value of work to be performed on contracts awarded and in progress. We had $4.2 billion of RUPO at March 29, 2026. Our RUPO increases with awards from new contracts or additions on existing contracts and decreases as work is performed and revenue is recognized on existing contracts. Our RUPO may also decrease when projects are canceled or modified in scope. We include a contract within our RUPO when the contract is awarded and an agreement on contract terms has been reached. Although RUPO reflects business that is considered to be firm, cancellations, deferrals or scope adjustments may occur. Our RUPO is adjusted to reflect any known project cancellations, revisions to project scope and cost, foreign currency exchange fluctuations and project deferrals, as appropriate. Our operations and maintenance contracts can generally be terminated by the clients without a substantive financial penalty; therefore, the remaining performance obligations on such contracts are limited to the notice period required for the termination (usually 30, 60, or 90 days).
Accounts Receivable, Net	Billed accounts receivable represent amounts billed to clients that have not yet been collected. Unbilled accounts receivable, which represent an unconditional right to payment subject only to the passage of time, include unbilled amounts typically resulting from revenue recognized but not yet billed pursuant to contract terms or billed after the period end date. Substantially all of our unbilled receivables at March 29, 2026 are expected to be billed and collected within 12 months. The allowance for doubtful accounts represents amounts that are expected to become uncollectible or unrealizable in the future. We estimate the allowance for uncollectible accounts based on management's consideration of trends in the actual and forecasted credit quality of our clients, including client delinquency and payment history; type of client, such as a government agency or a commercial sector client; and general economic and industry conditions that may affect our clients' ability to pay.
Fair Value Measurements	We classified our assets and liabilities that were carried at fair value in one of the following categories: •Level 1: Quoted market prices in active markets for identical assets or liabilities. •Level 2: Observable market-based inputs or unobservable inputs that are corroborated by market data. •Level 3: Unobservable inputs that are not corroborated by market data. Contingent Consideration. We measure our contingent earn-out liabilities at fair value on a recurring basis using significant unobservable inputs classified within Level 3 of the fair value hierarchy (see Note 4, "Acquisitions and Divestitures" for further information). Debt. The fair value of long-term debt under our credit facility was determined using the present value of future cash flows based on the borrowing rates currently available for debt with similar terms and maturities (Level 2 measurement, as described in “Critical Accounting Policies and Estimates” in our Annual Report on Form 10-K for the fiscal year ended September 28, 2025). The carrying value of our long-term debt under our credit facility approximated fair value at March 29, 2026 and September 28, 2025.

Recent Accounting Pronouncements (Policies)

6 Months Ended

Mar. 29, 2026

Accounting Changes and Error Corrections [Abstract]

In September 2025, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update (“ASU”) No. 2025-06, Intangibles - Goodwill and Other - Internal-Use Software (Subtopic 350-40): Targeted Improvements to the Accounting for Internal-Use Software, which clarifies and modernizes the accounting for costs related to internal-use software guidance in subtopic 350-40. The guidance removes all references to project stages throughout Accounting Standards Codification ("ASC") 350-40 and clarifies the threshold entities apply to begin capitalizing costs. The amendments in this ASU are effective for annual periods beginning after December 15, 2027 (fiscal 2029 for us). Early adoption is permitted. We are currently evaluating the impact of this guidance on our consolidated financial statements; however, we do not plan to adopt it before fiscal 2029.

In July 2025, the FASB issued ASU No. 2025-05, Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Loss for Accounts Receivable and Contract Assets, which provides a practical expedient (for all entities) and an accounting policy election (for all entities, other than public business entities, that elect the practical expedient) related to the estimation of expected credit losses for current accounts receivable and current contract assets that arise from transactions accounted for under ASC Topic 606, "Revenue from Contracts with Customers". The amendments in this ASU are effective for annual periods beginning after December 15, 2025 (fiscal 2027 for us). Early adoption is permitted. We are currently evaluating the impact of this guidance on our consolidated financial statements; however, we do not plan to adopt it before fiscal 2027.

In December 2023, the FASB issued ASU No. 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures, which requires entities to disclose additional income tax information on an annual basis, primarily related to the rate reconciliation and income taxes paid. The amendments in the ASU are intended to enhance the transparency and decision usefulness of income tax disclosures. The amendments in this ASU are effective for annual periods beginning after December 15, 2024 (fiscal 2026 for us). The adoption of this ASU will not have a material impact on our consolidated financial statements.

In November 2024, the FASB issued ASU No. 2024-03, Income Statement (Topic 220): Reporting Comprehensive Income. ASU 2024-03 does not change or remove current expense presentation requirements within the consolidated statements of income. However, the amendments require disclosure, on an annual and interim basis, of disaggregated information about certain income statement expense line items within the notes to the consolidated financial statements. The amendments in this update are effective for annual reporting periods beginning after December 15, 2026 (fiscal 2028 for us), and interim reporting periods beginning after December 15, 2027 (first quarter of fiscal 2029 for us). Early adoption is permitted. The adoption of this ASU will not have a material impact on our consolidated financial statements.

In November 2024, the FASB issued ASU No. 2024-04, Debt—Debt with Conversion and Other Options (Subtopic 470-20): Induced Conversions of Convertible Debt Instruments, which clarifies the requirements related to accounting for the settlement of a debt instrument as an induced conversion. The amendments in this update are effective for annual reporting periods beginning after December 15, 2025, including interim periods within those fiscal years (first quarter of fiscal 2027 for us). Early adoption is permitted. We are currently evaluating the impact of this guidance on our consolidated financial statements; however, we do not plan to adopt this ASU before fiscal 2027.

Contract Assets and Contract Liabilities and Remaining Unsatisfied Performance Obligation (“RUPO”)

We invoice customers based on the contractual terms of each contract. However, the timing of revenue recognition may differ from the timing of invoice issuance. Contract assets represent revenue recognized in excess of the amounts for which we have the contractual right to bill our customers. Such amounts are recoverable from customers based upon various measures of performance, including achievement of certain milestones or completion of a contract. In addition, many of our time-and-materials arrangements are billed in arrears pursuant to contract terms that are standard within the industry, resulting in contract assets and/or unbilled receivables being recorded, as revenue is recognized in advance of billings. Contract retentions, included in contract assets, represent amounts withheld by clients until certain conditions are met or the project is completed, which may extend beyond one year.

Contract liabilities consist of billings in excess of revenue recognized. Contract liabilities decrease as we recognize revenue from the satisfaction of the related performance obligation and increase as billings in advance of revenue recognition occur. Contract assets and liabilities are reported in a net position on a contract-by-contract basis at the end of each reporting period. There were no substantial non-current contract assets for the periods presented.Revenue is recognized by measuring progress over time under Accounting Standards Codification Topic 606, "Revenue from Contracts with Customers". We estimate and measure progress on our contracts over time whereby we compare our total costs incurred on each contract as a percentage of the total expected contract costs. Changes in those estimates could result in the recognition of cumulative catch-up adjustments to the contract’s inception-to-date revenue, costs and profit in the period in which such changes are made.

Remaining Unsatisfied Performance Obligation (“RUPO”)

Our RUPO represents a measure of the total dollar value of work to be performed on contracts awarded and in progress. We had $4.2 billion of RUPO at March 29, 2026. Our RUPO increases with awards from new contracts or additions on existing contracts and decreases as work is performed and revenue is recognized on existing contracts. Our RUPO may also decrease when projects are canceled or modified in scope. We include a contract within our RUPO when the contract is awarded and an agreement on contract terms has been reached.

Although RUPO reflects business that is considered to be firm, cancellations, deferrals or scope adjustments may occur. Our RUPO is adjusted to reflect any known project cancellations, revisions to project scope and cost, foreign currency exchange fluctuations and project deferrals, as appropriate. Our operations and maintenance contracts can generally be terminated by the clients without a substantive financial penalty; therefore, the remaining performance obligations on such contracts are limited to the notice period required for the termination (usually 30, 60, or 90 days).

Accounts Receivable, Net

Billed accounts receivable represent amounts billed to clients that have not yet been collected. Unbilled accounts receivable, which represent an unconditional right to payment subject only to the passage of time, include unbilled amounts typically resulting from revenue recognized but not yet billed pursuant to contract terms or billed after the period end date. Substantially all of our unbilled receivables at March 29, 2026 are expected to be billed and collected within 12 months. The allowance for doubtful accounts represents amounts that are expected to become uncollectible or unrealizable in the future. We estimate the allowance for uncollectible accounts based on management's consideration of trends in the actual and forecasted credit quality of our clients, including client delinquency and payment history; type of client, such as a government agency or a commercial sector client; and general economic and industry conditions that may affect our clients' ability to pay.

Fair Value Measurements

We classified our assets and liabilities that were carried at fair value in one of the following categories:

•Level 1: Quoted market prices in active markets for identical assets or liabilities.

•Level 2: Observable market-based inputs or unobservable inputs that are corroborated by market data.

•Level 3: Unobservable inputs that are not corroborated by market data.

Contingent Consideration. We measure our contingent earn-out liabilities at fair value on a recurring basis using significant unobservable inputs classified within Level 3 of the fair value hierarchy (see Note 4, "Acquisitions and Divestitures" for further information).

Debt. The fair value of long-term debt under our credit facility was determined using the present value of future cash flows based on the borrowing rates currently available for debt with similar terms and maturities (Level 2 measurement, as described in “Critical Accounting Policies and Estimates” in our Annual Report on Form 10-K for the fiscal year ended September 28, 2025). The carrying value of our long-term debt under our credit facility approximated fair value at March 29, 2026 and September 28, 2025.