Warranty Liability (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2019	Dec. 31, 2018
Warranty liability
Period of warranty history used in estimating warranty costs	5 years
Other long-term liabilities				$ 19,818	$ 14,856
Accrued expenses and other current liabilities				26,496	23,306
warranty reserve	$ 6,174	$ 5,677	$ 6,160	6,541	6,174
Company's warranty liability:
Balance at the beginning of the period	6,174	5,677	6,160
Warranty provision	3,953	4,076	2,506
Claims paid/settlements	(3,586)	(3,579)	(3,054)
Balance at the end of the period	$ 6,541	$ 6,174	5,677
Warranty Reserves
Warranty liability
Other long-term liabilities				2,600	2,512
Accrued expenses and other current liabilities				$ 3,941	$ 3,662
Henderson
Company's warranty liability:
Establish warranty provision for acquired companies			$ 65
Snow and ice control equipment
Warranty liability
Warranty period	2 years
Parts and accessories
Warranty liability
Warranty period	1 year
Certain snowplows
Warranty liability
Warranty period	1 year