Amounts Reclassified Out of Accumulated Other Comprehensive Income - Reclassification out of accumulated other comprehensive (loss) income (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Jun. 25, 2016	Jun. 27, 2015	Jun. 25, 2016	Jun. 27, 2015
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance beginning		$ (45,971)	$ (44,013)	$ (48,883)	$ (45,905)
Other comprehensive income before reclassifications		(107)	(128)	(47)	(855)
Reclassifications to earnings		1,382	1,302	4,234	3,921
Other comprehensive income		1,275	1,174	4,187	3,066
Balance ending		(44,696)	(42,839)	(44,696)	(42,839)
Cash Flow Hedges [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance beginning		(659)	(1,566)	(1,311)	(1,540)
Other comprehensive income before reclassifications		(107)	(128)	(47)	(855)
Reclassifications to earnings	[1]	252	342	844	1,043
Other comprehensive income		145	214	797	188
Balance ending		(514)	(1,352)	(514)	(1,352)
Pension Benefits [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance beginning		(50,227)	(46,773)	(52,836)	(49,034)
Other comprehensive income		1,304	1,131	3,913	3,392
Balance ending		(48,923)	(45,642)	(48,923)	(45,642)
Amortization of Net Loss [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Reclassifications to earnings	[2]	1,304	1,131	3,913	3,392
Post-Retirement Benefits [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance beginning		4,915	4,326	5,264	4,669
Other comprehensive income		(174)	(171)	(523)	(514)
Balance ending		4,741	4,155	4,741	4,155
Amortization of Prior Service Credits [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Reclassifications to earnings	[2]	(100)	(122)	(300)	(367)
Amortization of Net (Gain) [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Reclassifications to earnings	[2]	$ (74)	$ (49)	$ (223)	$ (147)

[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 13, “Pension Plans and Other Postretirement Benefits”.