Retirement Plans (Components Of Net Periodic Benefit Cost) (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 27, 2015	Sep. 28, 2014	Sep. 29, 2013
Qualified Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 7,592	$ 7,633	$ 10,210
Interest cost	19,750	20,196	19,964
Expected return on plan assets	(23,273)	(24,492)	(22,715)
Actuarial loss	8,278	3,575	15,665
Net periodic benefit cost	12,347	6,912	23,124
Postretirement Health Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	0	0
Interest cost	1,196	1,639	1,586
Actuarial loss	182	542	791
Net periodic benefit cost	1,378	2,181	2,377
Supplemental Employee Retirement Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	676	490	543
Interest cost	2,945	3,049	2,664
Actuarial loss	1,134	859	2,170
Amortization of unrecognized prior service cost	269	269	269
Net periodic benefit cost	$ 5,024	$ 4,667	$ 5,646