Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Cash Flows from Operating Activities:
Net Income	$ 86,148	$ 103,500	$ 137,061
Adjustments to reconcile Net Income to net cash from operating activities:
Depreciation	32,193	21,380	21,292
Amortization of intangible assets and debt issuance costs	15,438	9,954	17,215
Stock-based compensation expense	8,818	12,752	12,462
Adjustment of investments to fair value	4,750	5,742	(39)
Excess income tax benefit from stock-based compensation	(18)	(218)	(28)
Deferred income taxes	10,854	(3,826)	(10,541)
Gain on bargain purchase	(47)	0	0
(Gain) loss on sale of assets	(716)	1,274	964
Other assets	(601)	(86)	0
Other long-term liabilities	(12,723)	(4,623)	(36,284)
(Increase) decrease in:
Accounts receivable	6,657	(22,054)	363,076
Costs and estimated earnings in excess of billings	(80,670)	7,144	(29,798)
Other current assets	6,631	(4,690)	(11,017)
Increase (decrease) in:
Accounts payable	(45,278)	(101,143)	(449,370)
Billings in excess of costs and estimated earnings	(25,310)	11,957	(8,928)
Accrued expenses	(36,650)	(10,791)	(32,112)
NET CASH (USED) PROVIDED BY OPERATING ACTIVITIES	(30,524)	26,272	(26,047)
Cash Flows from Investing Activities:
Acquisitions, net of cash balance acquired	(341,898)	(30,924)	(6,900)
Business acquisition related payments	(3,000)	(6,734)	0
Acquisition of property and equipment	(66,747)	(25,200)	(37,005)
Proceeds from sale of property and equipment	10,049	1,811	1,873
Sales of land, net	0	0	203
Proceeds from sale of available-for-sale securities	30,191	7,066	3,641
Change in restricted cash	(6,816)	(23,550)	0
Investment in other activities	0	0	(2,698)
NET CASH USED BY INVESTING ACTIVITIES	(378,221)	(77,531)	(40,886)
Cash Flows from Financing Activities:
Proceeds from issuance of senior unsecured notes, net of debt discount	0	297,774	0
Proceeds from other debt	701,753	6,803	180,182
Repayment of other debt	(554,969)	(35,760)	(150,625)
Purchase of common stock under share repurchase program	0	(39,391)	0
Common stock dividend paid	0	(47,090)	0
Excess income tax benefit from stock-based compensation	18	218	28
Issuance of Common stock and effect of cashless exercise	(191)	(325)	173
Debt issuance costs	(5,004)	(7,901)	(688)
NET CASH PROVIDED BY FINANCING ACTIVITIES	141,607	174,328	29,070
Net (Decrease) Increase in Cash and Cash Equivalents	(267,138)	123,069	(37,863)
Cash and Cash Equivalents at Beginning of Year	471,378	348,309	386,172
Cash and Cash Equivalents at End of Year	204,240	471,378	348,309
Supplemental Disclosure of Cash Paid During the Year For:
Interest	31,379	6,151	7,804
Income taxes	53,055	48,421	83,747
Supplemental Disclosure of Non-Cash Transactions:
Grant date fair value of common stock issued for services	5,608	19,673	7,411
Assets acquired through financing arrangements	$ 1,604	$ 10,784	$ 5,734