Amounts Reclassified Out of Accumulated Other Comprehensive Income - Reclassification out of accumulated other comprehensive income (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Jun. 27, 2015	Jun. 28, 2014	Jun. 27, 2015	Jun. 28, 2014
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance beginning		$ (44,013)	$ (45,000)	$ (45,905)	$ (47,353)
Other comprehensive income before reclassifications		(128)	(433)	(855)	(689)
Reclassifications to earnings		1,302	1,306	3,921	3,915
Other comprehensive income		1,174	873	3,066	3,226
Balance ending		(42,839)	(44,127)	(42,839)	(44,127)
Cash Flow Hedges [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance beginning		(1,566)	(1,985)	(1,540)	(2,428)
Other comprehensive income before reclassifications		(128)	(433)	(855)	(689)
Reclassifications to earnings	[1]	342	351	1,043	1,050
Other comprehensive income		214	(82)	188	361
Balance ending		(1,352)	(2,067)	(1,352)	(2,067)
Pension Benefits [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance beginning		(46,773)	(47,741)	(49,034)	(49,987)
Other comprehensive income		1,131	1,123	3,392	3,369
Balance ending		(45,642)	(46,618)	(45,642)	(46,618)
Amortization of Net Loss [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Reclassifications to earnings	[2]	1,131	1,123	3,392	3,369
Post-Retirement Benefits [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance beginning		4,326	4,726	4,669	5,062
Other comprehensive income		(171)	(168)	(514)	(504)
Balance ending		4,155	4,558	4,155	4,558
Amortization of Prior Service Costs [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Reclassifications to earnings	[2]	(122)	(122)	(367)	(367)
Amortization of Net (Gain) [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Reclassifications to earnings	[2]	$ (49)	$ (46)	$ (147)	$ (137)

[1] Reclassification of realized losses on cash flow hedges are recognized in interest expense.

[2] These amounts are included in the computation of net periodic benefit cost. See Note 12, “Pension Plans and Other Postretirement Benefits”.