Revenue - Percentages of Sales by End Market (Details) - End Market - Sales	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Percentage of Sales by End Market [Line Items]
Percentage of sales	100.00%	100.00%	100.00%
Manufacturing
Percentage of Sales by End Market [Line Items]
Percentage of sales	62.40%	67.50%	66.70%
Non-residential construction
Percentage of Sales by End Market [Line Items]
Percentage of sales	11.30%	12.90%	13.10%
Other
Percentage of Sales by End Market [Line Items]
Percentage of sales	26.30%	19.60%	20.20%