Nature of Operations and Summary of Significant Accounting Policies - Revenue Recognition by Product Line, Product Type, Geography and Revenue Recognition Method (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 29, 2018	Sep. 30, 2017	Sep. 29, 2018	Sep. 30, 2017
Disaggregation of Revenue [Line Items]
Revenues	$ 165,745	$ 152,794	$ 469,851	$ 365,893
Point in Time [Member]
Disaggregation of Revenue [Line Items]
Revenues	148,524		436,527
Over Time [Member]
Disaggregation of Revenue [Line Items]
Revenues	17,221		33,324
North America [Member]
Disaggregation of Revenue [Line Items]
Revenues	74,089	68,369	227,080	170,092
Europe [Member]
Disaggregation of Revenue [Line Items]
Revenues	44,912	46,475	131,437	113,178
Asia [Member]
Disaggregation of Revenue [Line Items]
Revenues	32,887	25,215	78,537	53,658
Rest of World [Member]
Disaggregation of Revenue [Line Items]
Revenues	13,857	12,735	32,797	28,965
Parts and Consumables [Member]
Disaggregation of Revenue [Line Items]
Revenues	92,749	83,755	283,591	224,239
Capital [Member]
Disaggregation of Revenue [Line Items]
Revenues	72,996	69,039	186,260	141,654
Operating Segment [Member] | Papermaking Systems [Member]
Disaggregation of Revenue [Line Items]
Revenues	126,770	111,135	350,811	295,416
Operating Segment [Member] | Papermaking Systems [Member] | Stock preparation [Member]
Disaggregation of Revenue [Line Items]
Revenues	62,983	52,065	164,842	139,396
Operating Segment [Member] | Papermaking Systems [Member] | Fluid handling [Member]
Disaggregation of Revenue [Line Items]
Revenues	33,083	28,532	98,500	73,099
Operating Segment [Member] | Papermaking Systems [Member] | Doctoring, Cleaning and Filtration [Member]
Disaggregation of Revenue [Line Items]
Revenues	30,704	30,538	87,469	82,921
Operating Segment [Member] | Wood Processing Systems Segment [Member]
Disaggregation of Revenue [Line Items]
Revenues	37,042	39,714	109,335	61,050
Corporate And Reconciling Items [Member] | Fiber based Products [Member]
Disaggregation of Revenue [Line Items]
Revenues	$ 1,933	$ 1,945	$ 9,705	$ 9,427