CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Cash Flows from Operating Activities:
Net income	$ 100,856	$ 55,600	$ 220,647	$ 73,608
Adjustments to reconcile net income to net cash provided by (used in) operating activities -
Depreciation	32,443	29,135	94,086	86,499
Amortization of intangible assets	10,504	8,295	29,447	21,432
Equity in earnings of unconsolidated affiliate	(1,308)		(1,308)
Amortization of debt issuance costs	228	182	678	419
Amortization of deferred revenues	(2,523)	(2,776)	(7,663)	(8,624)
Gain (loss) on sale of property and equipment	(253)	510	(858)	444
Foreign currency loss	243	700	617	901
Provision for doubtful accounts	468	19	2,827	855
Deferred income tax provision	9,118	11,683	12,037	21,775
Non-cash stock-based compensation	7,138	4,716	21,713	16,210
Tax impact of stock-based equity awards	66	303	24	(1,227)
Changes in operating assets and liabilities, net of non-cash transactions - (Increase) decrease in -
Accounts and notes receivable	(302,085)	(196,598)	(347,500)	(251,882)
Costs and estimated earnings in excess of billings on uncompleted contracts	(25,267)	(19,466)	(169,755)	7,444
Inventories	2,003	(11,150)	17,803	(21,445)
Prepaid expenses and other current assets	(27,213)	28,119	(17,518)	2,647
Increase (decrease) in -
Accounts payable and accrued expenses and other non-current liabilities	132,076	102,854	129,748	107,935
Billings in excess of costs and estimated earnings on uncompleted contracts	5,068	30,063	(10,911)	39,321
Other, net	(1,332)	(1,404)	(3,823)	(3,557)
Net cash provided by (used in) operating activities	(59,770)	40,785	(29,709)	92,755
Cash Flows from Investing Activities:
Proceeds from sale of property and equipment	2,326	4,797	9,781	9,380
Additions of property and equipment	(71,056)	(43,077)	(160,355)	(132,769)
Cash paid for acquisitions, net of cash acquired		(53,933)	(68,727)	(53,933)
Payments to acquire equity method investment			(53,750)	(35,000)
Cash paid for other investments		(4,000)		(4,000)
Cash paid for other intangibles	(1,541)	(455)	(1,541)	(455)
Net cash used in investing activities	(70,271)	(96,668)	(274,592)	(216,777)
Cash Flows from Financing Activities:
Borrowings under credit facility	425,540		775,160
Payments under credit facility	(339,540)		(650,160)
Proceeds from other long-term debt		318		4,343
Payments on other long-term debt	(14)	(1,470)	(47)	(5,646)
Debt issuance and amendment costs		(4,005)		(4,005)
Distributions to noncontrolling interests	(6,733)		(12,970)	(471)
Tax impact of stock-based equity awards	(66)	(303)	(24)	1,227
Exercise of stock options	649	60	1,573	555
Repurchase of common stock		(55,081)		(149,547)
Net cash provided by (used in) financing activities	79,836	(60,481)	113,532	(153,544)
Effect of foreign exchange rate changes on cash and cash equivalents	5,547	(6,180)	3,630	(3,817)
Net decrease in cash and cash equivalents	(44,658)	(122,544)	(187,139)	(281,383)
Cash and cash equivalents, beginning of period	172,868	380,382	315,349	539,221
Cash and cash equivalents, end of period	128,210	257,838	128,210	257,838
Cash (paid) received during the period for -
Interest paid	(752)	(120)	(1,532)	(446)
Income taxes paid	(40,255)	(880)	(111,179)	(6,890)
Income tax refunds	$ 384	$ 111	$ 2,677	$ 2,900