Segment Information - Revenue, Gross Profit and Cost of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 29, 2026	Mar. 30, 2025
Segment Reporting Information [Line Items]
Consolidated revenue	$ 723,174	$ 550,081
Consolidated gross profit	35,758	20,328
Consolidated cost of revenue	687,416	529,753
Operating Segments \| U.S. Gas
Segment Reporting Information [Line Items]
Consolidated revenue	284,499	197,694
Consolidated gross profit	(6,335)	(14,856)
Consolidated cost of revenue	290,834	212,550
Operating Segments \| Canadian Operations
Segment Reporting Information [Line Items]
Consolidated revenue	60,028	39,784
Consolidated gross profit	9,100	7,079
Consolidated cost of revenue	50,928	32,705
Operating Segments \| Union Electric
Segment Reporting Information [Line Items]
Consolidated revenue	204,069	175,468
Consolidated gross profit	18,234	11,813
Consolidated cost of revenue	185,835	163,655
Operating Segments \| Non-Union Electric
Segment Reporting Information [Line Items]
Consolidated revenue	174,578	137,135
Consolidated gross profit	14,759	16,292
Consolidated cost of revenue	$ 159,819	$ 120,843

The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities.

Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity.

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- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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