Goodwill and Intangibles (Details 2) (USD $)	3 Months Ended		9 Months Ended
	Jun. 30, 2013	Jul. 01, 2012	Jun. 30, 2013	Jul. 01, 2012	Sep. 30, 2012
Finite-lived intangible assets
Gross Amount	$ 208,322,000		$ 208,322,000		$ 167,528,000
Accumulated Amortization	(113,568,000)		(113,568,000)		(93,297,000)
Amortization expense for intangible assets	9,600,000	6,900,000	24,200,000	22,100,000
Estimated amortization expense
2013	8,742,000		8,742,000
2014	26,238,000		26,238,000
2015	19,069,000		19,069,000
2016	15,921,000		15,921,000
2017	13,488,000		13,488,000
Beyond	11,296,000		11,296,000
Total	94,754,000		94,754,000
Non-compete agreements
Finite-lived intangible assets
Weighted-Average Remaining Life			2 years 9 months 18 days
Gross Amount	6,174,000		6,174,000		5,467,000
Accumulated Amortization	(5,138,000)		(5,138,000)		(4,685,000)
Client relations
Finite-lived intangible assets
Weighted-Average Remaining Life			4 years 8 months 12 days
Gross Amount	128,399,000		128,399,000		99,096,000
Accumulated Amortization	(44,231,000)		(44,231,000)		(31,477,000)
Backlog
Finite-lived intangible assets
Weighted-Average Remaining Life			7 months 6 days
Gross Amount	69,640,000		69,640,000		59,931,000
Accumulated Amortization	(62,362,000)		(62,362,000)		(55,908,000)
Technology and trade names
Finite-lived intangible assets
Weighted-Average Remaining Life			3 years 1 month 6 days
Gross Amount	4,109,000		4,109,000		3,034,000
Accumulated Amortization	$ (1,837,000)		$ (1,837,000)		$ (1,227,000)