Retirement Plans - Periodic Pension Cost, Next Fiscal Year (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 25, 2016
Defined Benefit Plan Disclosure [Line Items]
Interest cost		$ 1,086	$ 1,189	$ 1,216
Net periodic pension cost		$ 1,524	$ 1,558	$ 1,551
Scenario, Forecast [Member]
Defined Benefit Plan Disclosure [Line Items]
Interest cost	$ 1,144
Amortization of actuarial loss	209
Net periodic pension cost	$ 1,353