Retirement Plans (Components Of Net Periodic Benefit Cost) (Details) - USD ($) $ in Thousands		4 Months Ended
		Jan. 21, 2018	Jan. 22, 2017
Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Interest cost		$ 6,879	$ 6,996
Service cost		687	673
Expected return on plan assets		(8,680)	(8,659)
Actuarial loss	[1]	1,498	1,881
Amortization of unrecognized prior service cost	[1]	45	47
Net periodic benefit cost		429	938
Postretirement Healthcare Plans
Defined Benefit Plan Disclosure [Line Items]
Interest cost		294	309
Actuarial loss	[1]	(8)	50
Net periodic benefit cost		$ 286	$ 359

[1] (1)Amounts were reclassified from accumulated OCI into net earnings as a component of selling, general and administrative expenses.