Changes in Accumulated Other Comprehensive Loss (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 26, 2020	Dec. 28, 2019	Dec. 29, 2018
Accumulated Other Comprehensive Income Loss [Line Items]
Balance	$ 735,636	$ 460,317	$ 423,523
Deferred pension and other post-retirement benefit costs	1,611	(442)	191
Amortization of Deferred benefit costs	(219)	(77)	86
One time effect of adoption of ASU 2018-02, Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income			(211)
Currency translation adjustment	25	47	25
Balance	956,967	735,636	460,317
AOCI Attributable to Parent
Accumulated Other Comprehensive Income Loss [Line Items]
Balance	(1,669)	(1,197)	(1,288)
Currency translation adjustment	25	47	25
Balance	$ (252)	$ (1,669)	$ (1,197)