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Industry Segments - Additional Information (Details)
$ in Thousands
3 Months Ended 12 Months Ended
Dec. 31, 2019
USD ($)
Sep. 30, 2019
USD ($)
Jun. 30, 2019
USD ($)
Mar. 31, 2019
USD ($)
Dec. 31, 2018
USD ($)
Sep. 30, 2018
USD ($)
Jun. 30, 2018
USD ($)
Mar. 31, 2018
USD ($)
Dec. 31, 2019
USD ($)
Segment
Dec. 31, 2018
USD ($)
Dec. 31, 2017
USD ($)
Segment Reporting Information [Line Items]                      
Number of operating segments | Segment                 2    
Net sales $ 116,818 $ 125,480 $ 134,285 $ 139,115 $ 138,388 $ 135,219 $ 140,560 $ 152,568 $ 515,698 $ 566,735 $ 547,043
Foreign Countries [Member]                      
Segment Reporting Information [Line Items]                      
Net sales                 42,000 50,600 53,900
Long-lived assets $ 13,200       $ 14,100       13,200 14,100  
Export Sales [Member] | Foreign Countries [Member]                      
Segment Reporting Information [Line Items]                      
Net sales                 $ 23,600 $ 19,600 $ 17,200
Sales [Member] | Customer Concentration Risk [Member] | Canada [Member]                      
Segment Reporting Information [Line Items]                      
Concentration risk percentage                 4.70% 4.10% 2.40%