Summary of Significant Accounting Policies - Additional Information (Detail) $ in Millions	12 Months Ended
	Dec. 31, 2019 USD ($) State Customer Agreement Segment Center	Dec. 31, 2018 USD ($) Segment	Dec. 31, 2017 USD ($)
Business And Summary Of Significant Accounting Policies [Line Items]
Number of distribution centers | Center	27
Number of states in which products are distributed | State	41
Allowance for doubtful accounts days	90 days
Inventory valuation LIFO method	88.00%	88.00%
First-In, First-Out cost higher than LIFO valuation	$ 19.2	$ 18.4
Company recorded depreciation expense	4.8	4.2	$ 3.7
Cost of sales	$ 650.0	$ 673.1	$ 597.4
Percentage of consolidated revenues of company's top ten clients	44.00%
Number of major customers | Customer	10
Percentage of employees represented under collective bargaining agreements	13.00%
Number of collective bargaining agreements | Agreement	8
Number of collective bargaining agreements expired in next year | Agreement	1
Aggregate number of reporting segment | Segment	1	1
Major Customer [Member]
Business And Summary Of Significant Accounting Policies [Line Items]
Total sales in percentage	15.00%	14.00%	14.00%
Shipping and Handling [Member]
Business And Summary Of Significant Accounting Policies [Line Items]
Cost of sales	$ 39.5	$ 38.4	$ 34.0
Minimum [Member] | Building and Improvements [Member]
Business And Summary Of Significant Accounting Policies [Line Items]
Building and improvements lives	3 years
Minimum [Member] | Machinery and Equipment [Member]
Business And Summary Of Significant Accounting Policies [Line Items]
Building and improvements lives	3 years
Maximum [Member] | Building and Improvements [Member]
Business And Summary Of Significant Accounting Policies [Line Items]
Building and improvements lives	25 years
Maximum [Member] | Machinery and Equipment [Member]
Business And Summary Of Significant Accounting Policies [Line Items]
Building and improvements lives	10 years