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	$ 21,897	$ 37,582	$ 36,583
Adjustments to reconcile net income to net cash flows provided by operating activities:
Bargain purchase gain, net of tax		(27,024)
Depreciation and amortization	104,100	76,736	38,889
Provision for doubtful accounts	14,822	17,261	1,402
Amortization of debt discount and debt issuance costs	1,962	1,428	503
Stock-based compensation	3,249	2,043	1,364
Deferred income taxes	27,580	(348)	1,620
Equity in earnings of unconsolidated affiliates	(3,029)	(743)
Gain on disposition of long-lived assets	(2,397)
Impairment of goodwill	2,425
Changes in operating assets and liabilities, excluding the effects of acquisitions:
Accounts receivable, net	(23,202)	(15,555)	(1,454)
Materials and supplies, prepayments, and other current assets	11,089	(26,281)	(791)
Prepaid income taxes	(1,922)		10,708
Accounts payable and accrued liabilities	(11,024)	52,261	5,606
Accrued taxes	(10,323)	(3,461)	(92)
Other	(2,624)	(11,098)	(1,712)
Net cash provided by operating activities	132,603	102,801	92,626
Cash flows from investing activities:
Capital expenditures	(101,401)	(135,688)	(59,719)
Acquisitions of businesses		(225,551)	(24)
Acquisitions of assets		(57)	(25)
Cash acquired in business combinations	4,087	53
Proceeds from disposition of long-lived assets	1,200
Decrease/(increase) in restricted cash	467	4,782	(5,248)
Sale/purchase of short term investments			2,956
Net cash used in investing activities	(95,647)	(356,461)	(62,060)
Cash flows from financing activities:
Dividends paid on common stock	(13,703)	(12,569)	(11,301)
Distribution to minority stockholders	(2,814)	(1,870)	(8,098)
Payment of debt issuance costs	(1,037)	(4,321)	(150)
Proceeds from stock option exercises	1,175	1,652	74
Principal repayments of term loan	(13,450)	(49,568)	(750)
Principal repayments of revolver loan	(132,911)
Purchase of common stock	(218)	(44)	(134)
Investments made by minority shareholders in consolidated affiliates	784	3,463	375
Proceeds from borrowings under term loan,		200,000
Proceeds from borrowings under revolver loan,	137,069	64,000
Repurchase of non-controlling interests	(446)
Net cash provided by (used in) financing activities	(25,551)	200,743	(19,984)
Net change in cash and cash equivalents	11,405	(52,917)	10,582
Cash and cash equivalents, beginning of year	37,330	90,247	79,665
Cash and cash equivalents, end of year	48,735	37,330	90,247
Supplemental cash flow information:
Interest paid	18,173	11,518	3,814
Taxes paid	$ 3,902	$ 24,974	$ 27,026