CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Current Assets:
Cash and cash equivalents	$ 53,303	$ 27,042
Receivables, net	112,416	110,777
Prepaid expenses and other current assets	9,053	9,138
Income taxes receivable	2,842
Total current assets	177,614	146,957
Property and equipment, net	232,317	234,432
Restricted cash and investments	4,887	5,802
Intangible assets, net	216,939	222,812
Goodwill	188,479	189,373
Other assets	4,427	2,700
Total assets	824,663	802,076
Current Liabilities:
Accounts payable	17,717	14,868
Deferred revenue	10,228	8,532
Accrued liabilities	30,404	22,888
Accrued salaries and benefits	11,838	14,242
Income taxes payable		2,970
Current portion of closure and post-closure obligations	2,299	2,330
Total current liabilities	72,486	65,830
Long-term closure and post-closure obligations	75,268	73,758
Long-term debt	277,000	277,000
Other long-term liabilities	1,811	3,828
Deferred income taxes, net	57,798	57,583
Total liabilities	484,363	477,999
Commitments and contingencies
Stockholders’ Equity:
Common stock $0.01 par value, 50,000 authorized; 21,976 and 21,849 shares issued, respectively	220	218
Additional paid-in capital	180,687	177,498
Retained earnings	170,112	155,533
Treasury stock, at cost, 8 and 3 shares, respectively	(370)	(68)
Accumulated other comprehensive loss	(10,349)	(9,104)
Total stockholders’ equity	340,300	324,077
Total liabilities and stockholders’ equity	$ 824,663	$ 802,076