Condensed Consolidated Statements of Cash Flows (Unaudited) (USD $) In Thousands	6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010
Operating activities
Net income	$ 16,503	$ 11,517
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	76,956	57,053
Equity compensation expense	11,483	7,847
Deferred income tax expense	2,058	7,250
Amortization of debt discount and issuance costs	6,945	6,300
Amortization of discontinued cash flow hedge from other comprehensive loss	1,879	2,918
Change in contingent consideration	(3,638)	(1,770)
Change in fair value of interest rate swap (not subject to hedge accounting)	(5,163)
Other	16	(50)
Changes in operating assets and liabilities:
Accounts receivable	(8,819)	814
Prepaid expenses and other	2,360	1,909
Accounts payable	3,925	(1,550)
Accrued expenses and other liabilities	399	(456)
Deferred revenues	417	(1,190)
Tax receivable agreement obligations to related parties	(2,913)	(1,480)
Net cash provided by operating activities	102,408	89,112
Investing activities
Purchases of property and equipment	(34,088)	(35,772)
Payments for acquisitions, net of cash acquired	(39,758)	(41,991)
Other		(3,000)
Net cash used in investing activities	(73,846)	(80,763)
Financing activities
Debt principal payments	(4,275)	(3,775)
Other	(1,015)	(104)
Net cash used in financing activities	(5,290)	(3,879)
Net increase in cash and cash equivalents	23,272	4,470
Cash and cash equivalents at beginning of period	99,188	211,999
Cash and cash equivalents at end of period	$ 122,460	$ 216,469