CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019
Cash flows from operating activities:
Net (loss) income	$ (303,269)	$ 23,534
Adjustments to reconcile net (loss) income to net cash provided by operating activities
Depreciation and amortization of property and equipment	36,396	17,254
Amortization of intangible assets	18,634	5,674
Accretion of closure and post-closure obligations	2,533	2,258
Property and equipment impairment charges		25
Goodwill impairment charges	300,300
Unrealized foreign currency loss (gain)	1,020	(502)
Deferred income taxes	(2,093)	3,690
Share-based compensation expense	3,088	2,467
Share-based payments of business development and integration expenses	973
Unrecognized tax benefits	52	131
Net loss (gain) on disposition of assets	188	(142)
Gain on insurance proceeds from damaged property and equipment		(9,153)
Amortization and write-off of debt issuance costs	679	409
Amortization and write-off of debt discount	490
Change in fair value of contingent consideration	(3,282)
Changes in assets and liabilities (net of effects of business acquisitions):
Receivables	43,619	(5,346)
Income taxes receivable	380	452
Other assets	(5,235)	(1,384)
Accounts payable and accrued liabilities	(32,218)	404
Deferred revenue	2,702	2,418
Accrued salaries and benefits	(6,481)	(2,025)
Income taxes payable	1,848	(515)
Closure and post-closure obligations	(798)	(775)
Net cash provided by operating activities	59,526	38,874
Cash flows from investing activities:
Business acquisitions (net of cash acquired)	(3,309)
Purchases of property and equipment	(35,957)	(24,657)
Insurance proceeds from damaged property and equipment		9,500
Proceeds from sale of property and equipment	788	512
Purchases of restricted investments	(902)	(400)
Proceeds from sale of restricted investments	752	354
Net cash used in investing activities	(38,628)	(14,691)
Cash flows from financing activities:
Proceeds from long-term debt	90,000
Payments on long-term debt	(2,250)	(30,000)
Payments on short-term borrowings	(68,375)	(14,384)
Proceeds from short-term borrowings	72,353	14,384
Repurchase of common stock	(18,332)
Dividends paid	(5,667)	(7,942)
Payment of acquired contingent consideration liabilities	(2,085)
Deferred financing costs paid	(1,026)
Payment of equipment financing obligations	(3,046)	(408)
Other	27	(914)
Net cash provided by (used in) financing activities	61,599	(39,264)
Effect of foreign exchange rate changes on cash	(1,303)	836
Increase (decrease) in Cash and cash equivalents and restricted cash	81,194	(14,245)
Cash and cash equivalents and restricted cash at beginning of period	42,140	32,753
Cash and cash equivalents and restricted cash at end of period	123,334	18,508
Supplemental Disclosures:
Income taxes paid, net of receipts	1,612	5,694
Interest paid	15,279	6,850
Non-cash investing and financing activities:
Capital expenditures in accounts payable	1,215	834
Restricted stock issued from treasury shares	$ 1,966	$ 451