Accounts Receivable, Net and Supplemental Balance-Sheet Information (Details) - USD ($) $ in Thousands	Jun. 29, 2024	Dec. 31, 2023
Accounts receivable, net
Accounts receivable	$ 263,206	$ 263,426
Unbilled receivables	113,219	99,485
Accounts receivable, gross	376,425	362,911
Less allowances for credit losses	4,843	2,441
Accounts receivable, net	371,582	360,470
Other current assets
Prepaid expenses	22,743	44,534
Mitigation bank credit inventory	27,478	28,385
Assets invested for self-insurance	23,913	20,959
Payroll taxes refundable	14,932	22,591
Other	169	302
Total	89,235	116,771
Property, Plant and Equipment, Net [Abstract]
Land and land improvements	28,437	28,177
Buildings and leasehold improvements	112,974	99,964
Equipment	725,685	684,562
Property, plant and equipment, gross	867,096	812,703
Less accumulated depreciation	503,722	500,025
Property and equipment, net	363,374	312,678
Other Assets, Noncurrent [Abstract]
Investment--cost-method affiliate	1,630	1,405
Deferred income taxes	6,024	6,001
Cloud computing arrangements	27	107
Other	6,407	4,362
Total	14,088	11,875
Accrued expenses
Employee compensation	33,343	40,656
Accrued compensated absences	15,609	14,483
Self-insured medical claims	4,541	2,309
Income tax payable	4,375	1,135
Customer advances, deposits	3,180	1,275
Taxes, other than income	9,679	6,017
Other	13,124	16,069
Total	83,851	81,944
Other current liabilities
Notes payable	0	543
Current operating lease liabilities	39,282	39,043
Current portion of long-term debt	25,008	40,429
Self-insurance accruals	49,682	50,379
Total	88,964	89,965
Other noncurrent liabilities
Non-qualified retirement plans	5,674	5,630
Other	5,496	6,096
Other noncurrent liabilities	$ 11,170	$ 11,726