Revenue Recognition - Summary of Disaggregated Net Sales (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 26, 2020	Dec. 28, 2019	Dec. 29, 2018
Disaggregation Of Revenue [Line Items]
Net Sales	$ 1,092,748	$ 991,329	$ 973,705
U.S. Customers [Member]
Disaggregation Of Revenue [Line Items]
Net Sales	1,031,183	929,908	913,181
Non-U.S. Customers [Member]
Disaggregation Of Revenue [Line Items]
Net Sales	61,565	61,421	60,524
Powertrain [Member]
Disaggregation Of Revenue [Line Items]
Net Sales	442,221	395,975	393,979
Chassis [Member]
Disaggregation Of Revenue [Line Items]
Net Sales	324,399	297,350	278,584
Automotive Body [Member]
Disaggregation Of Revenue [Line Items]
Net Sales	266,699	251,506	256,344
Hardware [Member]
Disaggregation Of Revenue [Line Items]
Net Sales	$ 59,429	$ 46,498	$ 44,798