Business Segment Information - Summary of Segment Information (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 28, 2019 USD ($)	Sep. 29, 2018 USD ($)	Sep. 28, 2019 USD ($) Segment	Sep. 29, 2018 USD ($)	Dec. 29, 2018 USD ($)
Segment Reporting [Abstract]
Number of reportable segments | Segment			3
Revenues:
Revenues	$ 173,504	$ 165,745	$ 521,985	$ 469,851
Income Before Provision for Income Taxes:
Total operating income	24,553	27,375	66,270	63,774
Interest expense, net	(3,023)	(1,708)	(9,985)	(4,985)
Other expense, net	(98)	(245)	(296)	(736)
Income Before Provision for Income Taxes	21,432	25,422	55,989	58,053
Capital Expenditures:
Capital expenditures	2,093	2,606	6,236	12,817
Total Assets:
Total Assets	935,557		935,557		$ 725,749
Restructuring costs	0	378	0	1,717
Operating Segment | Papermaking Systems
Revenues:
Revenues	118,503	126,770	347,785	350,811
Income Before Provision for Income Taxes:
Total operating income	22,798	25,919	61,368	61,402
Capital Expenditures:
Capital expenditures	1,376	1,348	3,890	9,837
Total Assets:
Total Assets	467,034		467,034		462,297
Restructuring costs		378		1,717
Operating Segment | Papermaking Systems | Stock-Preparation
Revenues:
Revenues	56,128	62,983	158,993	164,842
Operating Segment | Papermaking Systems | Fluid-Handling
Revenues:
Revenues	32,734	33,083	100,201	98,500
Operating Segment | Papermaking Systems | Doctoring, Cleaning, & Filtration
Revenues:
Revenues	29,641	30,704	88,591	87,469
Operating Segment | Wood Processing Systems
Revenues:
Revenues	32,731	37,042	104,649	109,335
Income Before Provision for Income Taxes:
Total operating income	6,787	8,704	22,858	21,380
Capital Expenditures:
Capital expenditures	444	1,026	1,423	2,586
Total Assets:
Total Assets	248,843		248,843		247,553
Acquisition transaction costs				252
Operating Segment | Material Handling Systems
Revenues:
Revenues	20,282	0	61,063	0
Income Before Provision for Income Taxes:
Total operating income	1,742	0	877	0
Capital Expenditures:
Capital expenditures	225	0	605	0
Total Assets:
Total Assets	198,423		198,423		0
Acquisition transaction costs	21		5,695
Corporate and Fiber-based Products
Income Before Provision for Income Taxes:
Total operating income	(6,774)	(7,248)	(18,833)	(19,008)
Capital Expenditures:
Capital expenditures	48	232	318	394
Total Assets:
Total Assets	21,257		21,257		$ 15,899
Corporate and Fiber-based Products | Fiber based Products
Revenues:
Revenues	$ 1,988	$ 1,933	$ 8,488	$ 9,705