Commitments and Contingencies (Details) $ in Millions	12 Months Ended
Dec. 28, 2025 USD ($) bankingInstitution	Dec. 29, 2024 USD ($)
Other Commitments [Line Items]
Number of financial banking institutions \| bankingInstitution	2
Performance and Payment Bond
Other Commitments [Line Items]
Outstanding performance and payment bonds	$ 822.8
Cost to complete bonded projects	385.9
Non-Union Electric Segment Customer \| Customer Concentration Risk \| Accounts Receivable and Contract Assets Benchmark
Other Commitments [Line Items]
Combined accounts receivable and contract assets	$ 131.9	$ 52.5
Concentration risk percentage	19.00%	10.00%

Accounts Receivable And Contract With Customer, Asset, After Allowance For Credit Loss, Current

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Number Of Financial Banking Institutions

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

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Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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