CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Cash flows from operating activities:
Net income	$ 9,361	$ 5,406
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization of property and equipment	3,839	3,439
Amortization of intangible assets	352	367
Accretion of closure and post-closure obligations	330	307
Unrealized foreign currency (gain) loss	1,452	1,057
Deferred income taxes	(460)	(716)
Share-based compensation expense	270	146
Unrecognized tax benefits	3	3
Net (gain) loss on sale of property and equipment	8	(41)
Changes in assets and liabilities:
Receivables	1,259	1,473
Other assets	882	732
Accounts payable and accrued liabilities	(2,142)	(556)
Deferred revenue	(1,164)	1,269
Accrued salaries and benefits	(1,994)	(3,106)
Income taxes payable	783	3,528
Closure and post-closure obligations	(114)	(1,043)
Net cash provided by operating activities	12,665	12,265
Cash flows from investing activities:
Purchases of property and equipment	(4,775)	(6,752)
Purchases of restricted cash and investments	(14)
Proceeds from sale of property and equipment	6	52
Net cash used in investing activities	(4,783)	(6,700)
Cash flows from financing activities:
Dividends paid	(3,874)
Proceeds from exercise of stock options	174	1,050
Payments on reducing revolving line of credit		(4,000)
Deferred financing costs paid		(177)
Other	(65)	2
Net cash used in financing activities	(3,765)	(3,125)
Effect of foreign exchange rate changes on cash	(139)	(49)
Increase in cash and cash equivalents	3,978	2,391
Cash and cash equivalents at beginning of period	73,940	2,120
Cash and cash equivalents at end of period	77,918	4,511
Supplemental Disclosures
Income taxes paid, net of receipts	4,934	378
Interest paid	40	184
Non-cash investing and financing activities:
Closure and post-closure retirement asset	2,863
Capital expenditures in accounts payable	419	1,645
Restricted stock issued from treasury shares	$ 118	$ 629