Amounts Reclassified Out of Accumulated Other Comprehensive Income - Reclassification out of accumulated other comprehensive (loss) income (Details) - USD ($) $ in Thousands		3 Months Ended
		Dec. 26, 2015	Dec. 27, 2014
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance beginning		$ (48,883)	$ (45,905)
Other comprehensive income before reclassifications		177	(227)
Reclassifications to earnings		1,292	1,316
Other comprehensive income		1,469	1,089
Balance ending		(47,414)	(44,816)
Cash Flow Hedges [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance beginning		(1,311)	(1,540)
Other comprehensive income before reclassifications		177	(227)
Reclassifications to earnings	[1]	333	357
Other comprehensive income		510	130
Balance ending		(801)	(1,410)
Pension Benefits [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance beginning		(52,836)	(49,034)
Other comprehensive income		1,134	1,130
Balance ending		(51,702)	(47,904)
Amortization of Net Loss [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Reclassifications to earnings	[2]	1,134	1,130
Post-Retirement Benefits [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance beginning		5,264	4,669
Other comprehensive income		(175)	(171)
Balance ending		5,089	4,498
Amortization of Prior Service Credits [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Reclassifications to earnings	[2]	(100)	(122)
Amortization of Net (Gain) [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Reclassifications to earnings	[2]	$ (75)	$ (49)

[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”.