Restructuring - Additional Information (Details) $ in Thousands	3 Months Ended	12 Months Ended
	Sep. 30, 2017 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($) facility
Restructuring Cost And Reserve [Line Items]
Expected restructuring charges in 2017		$ 7,600
Restructuring charges in employee severance and other employee-related costs		3,100
Restructuring charges in equipment relocation and facility shut down costs		2,500
Expected restructuring charges in accelerated depreciation charges on property, plant and equipment		2,000
Restructuring charges		7,553	$ 0	$ 2,411
Material Handling [Member]
Restructuring Cost And Reserve [Line Items]
Restructuring charges		7,553	0	$ 2,252
Number of manufacturing plants | facility				2
Held for Sale [Member]
Restructuring Cost And Reserve [Line Items]
Proceeds from the sale of assets	$ 6,000
Gain on asset dispositions	$ 2,600
Cost of Sales [Member]
Restructuring Cost And Reserve [Line Items]
Restructuring charges		7,389	0	$ 1,340
Other restructuring associated costs incurred		100
Cost of Sales [Member] | Material Handling [Member]
Restructuring Cost And Reserve [Line Items]
Restructuring charges		7,389	$ 0	$ 1,340
General and Administrative Expense
Restructuring Cost And Reserve [Line Items]
Other restructuring associated costs incurred		1,000
Manufacturing Plant Closing [Member]
Restructuring Cost And Reserve [Line Items]
Gains on other asset dispositions		1,500
Restructuring charges		5,500
Other restructuring associated costs incurred		1,100
Manufacturing Plant Closing [Member] | Sandusky, Ohio [member]
Restructuring Cost And Reserve [Line Items]
Restructuring charges		500
Headcount Efficiencies [Member]
Restructuring Cost And Reserve [Line Items]
Restructuring charges		3,022
Headcount Efficiencies [Member] | Cost of Sales [Member] | Scarborough, Ontario, Canada [Member]
Restructuring Cost And Reserve [Line Items]
Restructuring charges in employee severance and other employee-related costs		$ 1,600