Pension and Other Benefit Programs - Key Assumptions (Detail)	12 Months Ended
	Sep. 28, 2013	Sep. 29, 2012	Oct. 01, 2011
Schedule of Net Periodic Benefit Costs Weighted Average Assumptions [Line Items]
Year 1 increase in cost of benefits	7.25%
Rate of increase to which the cost of benefits is assumed to decline (the ultimate trend rate)	4.25%
Pension Plans
Schedule of Net Periodic Benefit Costs Weighted Average Assumptions [Line Items]
Discount rate	5.00%	3.85%	4.75%
Rate of return on plan assets	7.50%	7.75%	7.75%
Rate of salary increase	4.00%	4.00%	4.00%
Postretirement Medical Plans
Schedule of Net Periodic Benefit Costs Weighted Average Assumptions [Line Items]
Discount rate	5.00%	3.85%	4.75%
Rate of return on plan assets	7.50%	7.75%	7.75%
Year 1 increase in cost of benefits	7.25%	7.50%	8.00%
Rate of increase to which the cost of benefits is assumed to decline (the ultimate trend rate)	4.25%	4.50%	4.50%
Year that the rate reaches the ultimate trend rate	2027	2026	2025