Accounts Receivable, Net and Supplemental Balance-Sheet Information (Details) - USD ($) $ in Thousands	Apr. 02, 2022	Dec. 31, 2021
Accounts receivable, net
Accounts receivable	$ 199,440	$ 215,336
Unbilled receivables(1)	79,914	65,957
Accounts receivable, gross	279,354	281,293
Less allowances for credit losses	2,873	3,013
Accounts receivable, net	276,481	278,280
Other current assets
Refundable income taxes	2,158	1,346
Prepaid expenses	25,278	30,911
Certificates of deposits, current	3,750	4,250
Other	488	1,346
Total	31,674	37,853
Property, Plant and Equipment, Net [Abstract]
Land and Land Improvements	24,318	22,129
Buildings and leasehold improvements	66,962	63,933
Equipment	661,017	646,552
Property, Plant and Equipment, Gross	752,297	732,614
Less accumulated depreciation	508,936	504,629
Property and equipment, net	243,361	227,985
Other Assets, Noncurrent [Abstract]
Assets invested for self-insurance	34,957	25,401
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures	1,258	1,258
Deferred income taxes	5,086	4,937
Hosting Arrangement, Service Contract, Implementation Cost, Capitalized, after Accumulated Amortization	4,768	6,530
Other	4,516	4,539
Total	50,585	42,665
Accrued expenses
Employee compensation	17,354	37,828
Accrued compensated absences	11,577	11,007
Self-insured medical claims	3,715	2,891
Income tax payable	0	145
Customer advances, deposits	3,082	4,009
Taxes, other than income	17,853	13,789
Other	4,693	5,469
Total	58,274	75,138
Other current liabilities
Notes payable	533	0
Current operating lease liabilities	30,870	28,682
Current portion of long-term debt	13,969	22,809
Self-insurance accruals	47,741	48,867
Total	79,144	77,549
Other noncurrent liabilities
Non-qualified retirement plans	9,151	8,713
Other	3,032	2,870
Other noncurrent liabilities	$ 12,183	$ 11,583