Condensed Consolidated Balance Sheets (USD $) In Thousands	Sep. 30, 2011	Dec. 31, 2010
Current assets:
Cash and cash equivalents	$ 36,804	$ 164,203
Short-term investments	20,000	40,000
Restricted cash	0	345
Accounts receivable, net	238,050	186,001
Income tax receivable	928	9,443
Inventories	15,310	13,276
Prepaid and other current assets	6,738	3,542
Deferred income taxes	30,077	26,488
Total current assets	347,907	443,298
Property and equipment, net	347,465	338,778
Goodwill	1,368,085	1,258,065
Other	36,016	7,690
Total assets	2,099,473	2,047,831
Current liabilities:
Current installments of long-term obligations	104,710	619
Accounts payable	48,839	64,078
Accrued expenses:
Compensation and benefits	24,939	39,500
Liability insurance	17,219	19,052
Other current liabilities	60,137	51,501
Total current liabilities	255,844	174,750
Long-term obligations, excluding current installments	517,742	494,271
Deferred income taxes and other taxes	422,193	381,061
Total liabilities	1,195,779	1,050,082
Commitments and contingencies:
Stockholders' equity:
Common stock	889	963
Additional paid-in capital	703,873	681,988
Retained earnings	198,932	314,798
Total stockholders' equity	903,694	997,749
Total liabilities and stockholders' equity	$ 2,099,473	$ 2,047,831