Business Segments - Net Sales and Percentage of Consolidated Net Sales (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Concentration Risk [Line Items]
Net sales	$ 750,212	$ 704,134	$ 679,130	$ 619,163	$ 770,487	$ 737,671	$ 698,408	$ 601,496	$ 2,752,639	$ 2,808,062	$ 2,854,656
Customer Concentration Risk | American Tire Distributors, Inc. | Net Sales
Concentration Risk [Line Items]
Net sales									$ 311,559	$ 310,070	$ 252,395
Consolidated Net Sales									11.00%	11.00%	9.00%
Customer Concentration Risk | TBC/Treadways | Net Sales
Concentration Risk [Line Items]
Net sales									$ 214,138	$ 231,896	$ 304,840
Consolidated Net Sales									8.00%	8.00%	11.00%