Funded Status and Amounts Recognized in Consolidated Balance Sheets (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 30, 2017	Dec. 30, 2017	Dec. 31, 2016	Jan. 02, 2016
Change in plan assets:
Current liability	$ (935)	$ (935)	$ (979)
Noncurrent liability	(60,107)	(60,107)	(69,601)
Pension plans
Change in benefit obligation:
Benefit obligation at beginning of year		398,595	438,023
Service cost		755	830	$ 873
Interest cost		12,852	13,682	18,003
Actuarial loss (gain)		20,526	(13,076)
Benefits paid		(24,408)	(25,130)
Settlements		(14,368)	(15,734)
Benefit obligation at end of year	393,952	393,952	398,595	438,023
Change in plan assets:
Fair value of plan assets at beginning of year		335,663	370,497
Actual return on plan assets		42,076	4,689	6,900
Employer contribution		1,891	1,341	10,436
Benefits paid		(24,408)	(25,130)	(25,014)
Settlements		(14,368)	(15,734)
Fair value of plan assets at end of year	340,854	340,854	335,663	370,497
Benefits paid		(24,408)	(25,130)
Fair value of plan assets at end of year	340,854	340,854	335,663	370,497
Benefit obligation at end of year	393,952	393,952	398,595	438,023
Unfunded status and amount recognized at end of year	(53,098)	(53,098)	(62,932)
Current liability	(260)	(260)	(291)
Noncurrent liability	(52,838)	(52,838)	(62,641)
Amount recognized at end of year	(53,098)	(53,098)	(62,932)
Net actuarial (gain) loss before taxes	126,002	126,002	132,886
Prior service cost before taxes	5,426	5,426	5,813
Amount recognized at end of year	131,428	131,428	138,699
Accumulated benefit obligation at end of year	392,057	392,057	397,224
Postretirement Benefit Plans
Change in benefit obligation:
Benefit obligation at beginning of year		7,648	10,133
Service cost		256	401	398
Interest cost		227	309	360
Participant contributions	300	330	284	200
Actuarial loss (gain)		188	(2,354)
Benefits paid		(706)	(1,125)
Benefit obligation at end of year	7,943	7,943	7,648	10,133
Change in plan assets:
Employer contribution		376	841
Participant contributions	300	330	284	200
Benefits paid		(706)	(1,125)
Benefit obligation at end of year	7,943	7,943	7,648	$ 10,133
Unfunded status and amount recognized at end of year	(7,943)	(7,943)	(7,648)
Current liability	(674)	(674)	(688)
Noncurrent liability	(7,269)	(7,269)	(6,960)
Amount recognized at end of year	(7,943)	(7,943)	(7,648)
Net actuarial (gain) loss before taxes	(3,846)	(3,846)	(4,531)
Prior service cost before taxes	(262)	(262)	(474)
Accumulated benefit obligation at end of year	$ (4,108)	$ (4,108)	$ (5,005)