Components of Net Periodic Benefit Cost (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 13, 2024	Jul. 15, 2023	Jul. 13, 2024	Jul. 15, 2023
Pension plans
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 168	$ 157	$ 392	$ 367
Interest cost	272	301	634	702
Expected return on plan assets	(370)	(360)	(864)	(840)
Amortization of prior service cost (credit)	13	13	31	31
Amortization of net (gain) loss	10	40	23	93
Total net periodic pension cost (credit)	93	151	216	353
Postretirement Benefit Plan
Defined Benefit Plan Disclosure [Line Items]
Service cost	42	41	98	96
Interest cost	53	55	123	128
Amortization of prior service cost (credit)	(54)	(54)	(126)	(126)
Amortization of net (gain) loss	(42)	(57)	(97)	(133)
Total net periodic pension cost (credit)	$ (1)	$ (15)	$ (2)	$ (35)