| Accounts receivable net and supplemental balance-sheet information [Text Block] |
Accounts Receivable, Net and Supplemental Balance-Sheet Information Accounts receivable, net and other supplemental balance sheet information consisted of the following: | | | | | | | | | | | | | Accounts receivable, net | October 3,
2026 | | December 31,
2025 | | Accounts receivable | $ | 292,495 | | | $ | 271,949 | | Unbilled receivables (1) | 164,224 | | | 116,548 | | | 456,719 | | | 388,497 | | | Less allowances for credit losses | 1,897 | | | 3,027 | | | Accounts receivable, net | $ | 454,822 | | | $ | 385,470 | |
(1) Unbilled receivables consists of contract assets arising from revenue recognized but not yet billed in accordance with the terms of contracts, primarily with utility services customers. | | | | | | | | | | | | | Other current assets | October 3,
2026 | | December 31,
2025 | | Refundable income taxes | $ | 4,712 | | | $ | 9,184 | | | Prepaid expenses | 53,204 | | | 40,940 | | | | | | | Mitigation bank credit inventory | 29,467 | | | 32,453 | | | Assets invested for self-insurance | 10,566 | | | 12,576 | | | Payroll taxes refundable | — | | | 7,855 | | | Other | 1,853 | | | 1,519 | | | Total | $ | 99,802 | | | $ | 104,527 | |
| | | | | | | | | | | | | Property and equipment, net | October 3,
2026 | | December 31,
2025 | | Land and land improvements | $ | 57,028 | | | $ | 31,474 | | | Buildings and leasehold improvements | 162,272 | | | 177,279 | | | Equipment | 884,490 | | | 805,062 | | | 1,103,790 | | | 1,013,815 | | | Less accumulated depreciation | 575,293 | | | 542,615 | | | Total | $ | 528,497 | | | $ | 471,200 | |
| | | | | | | | | | | | | Other assets, noncurrent | October 3,
2026 | | December 31,
2025 | | Investment--cost-method affiliate | $ | 1,405 | | | $ | 1,405 | | | | | | | Cloud computing arrangements | 245 | | | 391 | | | | | | | Deposits and other | 10,267 | | | 8,152 | | | Total | $ | 11,917 | | | $ | 9,948 | |
| | | | | | | | | | | | | Accrued expenses | October 3,
2026 | | December 31,
2025 | | Employee compensation | $ | 42,565 | | | $ | 44,109 | | | Accrued compensated absences | 18,385 | | | 16,785 | | | Self-insured medical claims | 3,848 | | | 3,269 | | | Income tax payable | 913 | | | — | | | Customer advances, deposits | 2,022 | | | 1,254 | | | Taxes, other than income | 10,586 | | | 8,498 | | | | | | | Other | 9,407 | | | 13,956 | | | Total | $ | 87,726 | | | $ | 87,871 | |
| | | | | | | | | | | | | Other current liabilities | October 3,
2026 | | December 31,
2025 | | | | | | | | | | Current portion of: | | | | | Lease liability-operating leases | $ | 24,697 | | | $ | 28,920 | | | Acquisition consideration payable | 1,861 | | | — | | | Self-insurance accruals | 80,130 | | | 85,176 | | | Total | $ | 106,688 | | | $ | 114,096 | |
| | | | | | | | | | | | | Other noncurrent liabilities | October 3,
2026 | | December 31,
2025 | | Non-qualified deferred compensation and benefit plans | $ | 6,160 | | | $ | 5,699 | | | Deferred income taxes | 5,779 | | | 4,812 | | | | | | | Contingent consideration | 20,000 | | | — | | | Contract liabilities | 7,437 | | | 7,320 | | | Other | 3,704 | | | 3,622 | | | Total | $ | 43,080 | | | $ | 21,453 | |
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