Consolidated Statements of Cash Flows (USD $) In Thousands	6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 53,267	$ 36,595
Adjustments to reconcile net income to net cash provided by operating activities:
Loss from discontinued operations	0	72
Depreciation and amortization	32,158	24,900
Compensation cost related to equity awards	3,839	3,694
Excess tax benefit from share-based compensation	(2,049)	(969)
Deferred income taxes	11,071	12,063
Net gain on sale of assets	(2,098)	(1,848)
Gain on sale of investments	(894)	0
Gain on insurance recoveries	(1,043)	0
Insurance proceeds received	24	0
Changes in assets and liabilities which provided (used) cash, net of effect of acquisitions:
Accounts receivable trade, net	(17,612)	(5,796)
Materials and supplies	(1,763)	(314)
Prepaid expenses and other	2,048	(1,989)
Accounts payable and accrued expenses	(24,174)	8,526
Other assets and liabilities, net	(813)	(1,155)
Net cash provided by operating activities from continuing operations	51,961	73,779
Net cash used in operating activities from discontinued operations	(5)	(87)
Net cash provided by operating activities	51,956	73,692
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchase of property and equipment	(62,065)	(28,599)
Grant proceeds from outside parties	11,700	17,986
Cash paid for acquisition, net of cash acquired	(440)	0
Proceeds from sale of investments	1,369	208
Proceeds from disposition of property and equipment	3,106	3,293
Net cash used in investing activities from continuing operations	(46,330)	(7,112)
CASH FLOWS FROM FINANCING ACTIVITIES:
Principal payments on long-term borrowings, including capital leases	(115,764)	(13,637)
Proceeds from issuance of long-term debt	94,612	0
Debt amendment costs	0	1,641
Proceeds from employee stock purchases	12,631	5,219
Treasury stock purchases	(1,287)	(846)
Excess tax benefit from share-based compensation	2,049	969
Net cash used in financing activities from continuing operations	(7,759)	(9,936)
EFFECT OF EXCHANGE RATE CHANGES ON CASH AND CASH EQUIVALENTS	653	(3,147)
CHANGE IN CASH BALANCES INCLUDED IN CURRENT ASSETS OF DISCONTINUED OPERATIONS	1	87
(DECREASE) INCREASE IN CASH AND CASH EQUIVALENTS	(1,479)	53,584
CASH AND CASH EQUIVALENTS, beginning of period	27,417	105,707
CASH AND CASH EQUIVALENTS, end of period	$ 25,938	$ 159,291