CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Cash flows from operating activities:
Net income	$ 10,234	$ 16,455
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization of property and equipment	13,621	12,106
Amortization of intangible assets	5,286	5,256
Accretion of closure and post-closure obligations	2,155	2,049
Gain on disposition of business		(2,208)
Unrealized foreign currency gain	(425)	(685)
Deferred income taxes	(1,379)	(1,340)
Share-based compensation expense	1,959	1,578
Net loss on disposition of assets	245	22
Amortization and write-off of debt issuance costs	5,604	1,065
Amortization and write-off of debt discount	667	74
Changes in assets and liabilities:
Receivables	(14,486)	6,613
Income taxes receivable	2,020	(1,439)
Other assets	(4,038)	1,272
Accounts payable and accrued liabilities	5,819	(872)
Deferred revenue	4,770	(1,220)
Accrued salaries and benefits	(429)	787
Income taxes payable	(115)	49
Closure and post-closure obligations	(686)	(848)
Net cash provided by operating activities	30,822	38,714
Cash flows from investing activities:
Purchases of property and equipment	(17,552)	(14,488)
Business acquisition (net of cash acquired)		(4,934)
Purchases of restricted cash and investments	(820)	(1,043)
Proceeds from divestitures (net of cash divested)		2,723
Proceeds from sale of restricted cash and investments	802	973
Proceeds from sale of property and equipment	86	96
Net cash used in investing activities	(17,484)	(16,673)
Cash flows from financing activities:
Payments on long-term debt	(287,040)	(11,502)
Proceeds from long-term debt	281,000
Payment on short-term borrowings	(13,438)	(22,166)
Proceeds from short-term borrowings	11,260	26,132
Dividends paid	(7,849)	(7,835)
Proceeds from exercise of stock options	609	124
Payment of equipment financing obligations	(176)
Other	(77)	(162)
Net cash used in financing activities	(15,711)	(15,409)
Effect of foreign exchange rate changes on cash	260	168
Increase in cash and cash equivalents	(2,113)	6,800
Cash and cash equivalents at beginning of period	7,015	5,989
Cash and cash equivalents at end of period	4,902	12,789
Supplemental Disclosures
Income taxes paid, net of receipts	5,804	13,203
Interest paid	6,431	7,438
Non-cash investing and financing activities:
Capital expenditures in accounts payable	1,991	2,403
Restricted stock issued from treasury shares	$ 113	$ 415