Condensed Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Mar. 31, 2013	Apr. 01, 2012
Cash flows from operating activities:
Net income including noncontrolling interests	$ 51,268	$ 45,024
Adjustments to reconcile net income to net cash from operating activities:
Depreciation and amortization	29,322	29,071
Loss on settlement of foreign currency forward contract	270	286
Equity in income of unconsolidated joint ventures	(1,929)	(1,553)
Distributions of earnings from unconsolidated joint ventures	1,549	1,595
Stock-based compensation	4,840	5,648
Excess tax benefits from stock-based compensation	(866)	(147)
Deferred income taxes	4,880	(2,533)
Provision for doubtful accounts	2,164	3,721
Fair value adjustments to contingent consideration	(946)	(214)
Gain on disposal of property and equipment	(237)	(69)
Changes in operating assets and liabilities, net of effects of acquisitions:
Accounts receivable	75,183	11,038
Prepaid expenses and other assets	(4,139)	11,234
Accounts payable	(31,180)	(23,392)
Accrued compensation	(33,220)	(13,777)
Billings in excess of costs on uncompleted contracts	(15,732)	(1,156)
Other liabilities	(6,208)	10,791
Income taxes receivable/payable	(13,001)	(4,178)
Net cash provided by operating activities	62,018	71,389
Cash flows from investing activities:
Capital expenditures	(13,634)	(7,983)
Payments for business acquisitions, net of cash acquired	(168,092)	(2,831)
Payment in settlement of foreign currency forward contract	(4,177)	(4,192)
Receipt in settlement of foreign currency forward contract	3,907	3,906
Changes in restricted cash	470
Proceeds from sale of property and equipment	962	497
Net cash used in investing activities	(180,564)	(10,603)
Cash flows from financing activities:
Payments on long-term debt	(113,978)	(51,837)
Proceeds from borrowings	296,389	13,025
Payments of earn-out liabilities	(24,015)	(18,055)
Excess tax benefits from stock-based compensation	866	147
Net proceeds from issuance of common stock	14,561	8,882
Net cash provided by (used in) financing activities	173,823	(47,838)
Effect of foreign exchange rate changes on cash	(550)	2,585
Net increase in cash and cash equivalents	54,727	15,533
Cash and cash equivalents at beginning of period	104,848	90,494
Cash and cash equivalents at end of period	159,575	106,027
Cash paid during the period for:
Interest	2,494	2,839
Income taxes, net of refunds received	$ 31,531	$ 30,974