Selected Balance Sheet Information - Property Plant and Equipment (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Sep. 24, 2016
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	$ 1,372,128	$ 1,373,028
Less: accumulated depreciation	(679,501)	(630,899)
Property, plant and equipment, net	692,627	742,129
Land and improvements [Member]
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	192,256	193,194
Buildings and improvements [Member]
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	111,013	109,345
Transportation equipment [Member]
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	51,037	57,823
Storage facilities [Member]
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	110,573	110,528
Equipment, primarily tanks and cylinders [Member]
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	849,175	845,650
Computer software [Member]
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	53,826	52,643
Construction in progress [Member]
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	$ 4,248	$ 3,845