Pension Plans and Other Postretirement Benefits (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Dec. 27, 2014	Dec. 28, 2013
Components of net periodic benefit costs included in operating expenses [Abstract]
Projected annual contribution requirements related to the Partnership's postretirement health care and life insurance benefit plan for fiscal year	$ 1,276
Employer contribution for postretirement health care and life insurance	216
Partnership established accrual for estimated obligation to certain MEPPs	6,850
Number of voluntary partial withdrawal from multi employer pension plans	1
Number of full withdrawal from multi employer pension plans	4
Pension Benefits [Member]
Components of net periodic benefit costs included in operating expenses [Abstract]
Interest cost	1,282	1,443
Expected return on plan assets	(1,228)	(1,275)
Amortization of prior service costs	0	0
Amortization of net loss (gain)	1,130	1,123
Net periodic benefit cost	1,184	1,291
Postretirement Benefits [Member]
Components of net periodic benefit costs included in operating expenses [Abstract]
Interest cost	144	161
Expected return on plan assets	0	0
Amortization of prior service costs	(122)	(122)
Amortization of net loss (gain)	(49)	(46)
Net periodic benefit cost	$ (27)	$ (7)