Nature of Operations and Summary of Significant Accounting Policies - Goodwill (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 30, 2017	Dec. 31, 2016
Goodwill [Roll Forward]
Gross Balance, Beginning Balance	$ 236,964	$ 204,560
Accumulated impairment losses	(85,509)	(85,509)
Net Balance, Beginning Balance	151,455	119,051
Increase Due to Acquisition	101,881	38,552
Currency Translation	14,665	(6,148)
Goodwill period adjustments	116,546	32,404
Gross Balance, Ending Balance	353,510	236,964
Accumulated impairment losses	(85,509)	(85,509)
Net Balance, Ending Balance	268,001	151,455
Stock-Preparation
Goodwill [Roll Forward]
Net Balance, Beginning Balance	54,751
Net Balance, Ending Balance	60,275	54,751
Doctoring, Cleaning, & Filtration
Goodwill [Roll Forward]
Net Balance, Beginning Balance	33,839
Net Balance, Ending Balance	35,941	33,839
Fluid-Handling
Goodwill [Roll Forward]
Net Balance, Beginning Balance	45,600
Net Balance, Ending Balance	65,289	45,600
Operating Segments | Papermaking systems segment
Goodwill [Roll Forward]
Gross Balance, Beginning Balance	219,699	187,720
Accumulated impairment losses	(85,509)	(85,509)
Net Balance, Beginning Balance	134,190	102,211
Increase Due to Acquisition	16,373	38,552
Currency Translation	10,942	(6,573)
Goodwill period adjustments	27,315	31,979
Gross Balance, Ending Balance	247,014	219,699
Accumulated impairment losses	(85,509)	(85,509)
Net Balance, Ending Balance	161,505	134,190
Operating Segments | Wood Processing Systems
Goodwill [Roll Forward]
Gross Balance, Beginning Balance	17,265	16,840
Accumulated impairment losses	0	0
Net Balance, Beginning Balance	17,265	16,840
Increase Due to Acquisition	85,508	0
Currency Translation	3,723	425
Goodwill period adjustments	89,231	425
Gross Balance, Ending Balance	106,496	17,265
Accumulated impairment losses	0	0
Net Balance, Ending Balance	$ 106,496	$ 17,265