Mergers and Acquisitions (Details) (USD $)	3 Months Ended		9 Months Ended
	Jun. 30, 2013	Jul. 01, 2012	Jun. 30, 2013	Jul. 01, 2012	Sep. 30, 2012
Business acquisition
Aggregate maximum of contingent consideration	$ 115,500,000		$ 115,500,000
Gain on fair value adjustment for contingent earn-out liabilities	7,700,000	1,700,000	8,700,000	2,000,000
Contingent consideration accrued	91,000,000		91,000,000
Contingent consideration accrued as part of Estimated contingent earn-out liabilities	24,178,000		24,178,000		35,407,000
Contingent consideration accrued as part of Long-term estimated contingent earn-out liabilities	68,140,000		68,140,000		16,132,000
Earn-outs paid to former owners			24,400,000	30,400,000
Reported as cash used in financing activities			24,000,000	18,100,000
Reported as cash used in operating activities			400,000	600,000
Reported as cash used in investing activities				11,700,000
Maximum
Business acquisition
Earn out period for operating income projection			3 years
Minimum
Business acquisition
Earn out period for operating income projection			2 years
Prior to 2010 acquisitions
Business acquisition
Aggregate maximum of contingent consideration	3,000,000		3,000,000
AEG, Parkland and other 2013 acquisitions
Business acquisition
Aggregate fair value of purchase prices	244,400,000		244,400,000
Cash paid to the sellers	170,300,000		170,300,000
Amount receivable	1,100,000		1,100,000
Estimated fair value of contingent earn-out obligations	75,300,000		75,300,000
Aggregate maximum of contingent consideration	86,700,000		86,700,000
2012 acquisitions
Business acquisition
Aggregate fair value of purchase prices					63,200,000
Cash paid to the sellers					42,200,000
Amount accrued					2,000,000
Estimated fair value of contingent earn-out obligations					19,000,000
Aggregate maximum of contingent consideration					$ 20,000,000