Retirement Plans - Components of Net Pension Expense and Periodic Benefit Costs (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Jun. 30, 2013	Jun. 24, 2012	Jun. 30, 2013	Jun. 24, 2012
Compensation and Retirement Disclosure [Abstract]
Expected return on assets	$ (1,150)	$ (1,024)	$ (3,502)	$ (3,071)
Service cost	1,209	975	3,667	2,926
Interest cost	1,130	1,092	3,359	3,275
Amortization of prior service cost	0	0	2	2
Amortization of recognized losses	789	528	2,240	1,585
Net pension expense	$ 1,978	$ 1,571	$ 5,766	$ 4,717