Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
OPERATING ACTIVITIES:
Net income	$ 42,295	$ 41,704
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and other	36,740	34,323
Stock-based compensation expense	10,084	9,190
Impairment loss	1,144	0
Amortization of debt discount and deferred issuance costs	1,367	3,355
Change in fair value of acquisition contingencies	626	745
Accretion of interest on deferred consideration	6,352	7,686
Amortization of inventory step-up to fair value	0	3,650
Loss on extinguishment of debt	748	8,262
Changes in assets and liabilities:
Accounts receivable	(19,344)	257
Inventories	5,395	155
Prepaid expenses and other current and non-current assets	4,942	(20,328)
Accounts payable	4,429	633
Accrued payroll and related expenses	(5,780)	(24)
Other current and non-current liabilities	(2,237)	3,520
Net cash provided by operating activities:	86,761	93,128
INVESTING ACTIVITIES:
Acquisitions of property and equipment	(18,716)	(22,875)
Proceeds from sale of Summers Ridge Property	0	146,644
Net cash (used for) provided by investing activities:	(18,716)	123,769
FINANCING ACTIVITIES:
Proceeds from issuance of common stock	13,156	16,031
Payment of debt issuance costs	0	(513)
Payments on Revolving Credit Facility	(262)	(93)
Payments on finance lease obligation	(45,000)	(10,000)
Repurchases of common stock	(1,900)	(3,790)
Payments of acquisition contingent consideration	(4,044)	(6,294)
Payments of deferred consideration	(44,000)	(46,000)
Payments of Term Loan	0	(161,813)
Transaction costs related to debt exchange	(733)	(2,002)
Net cash used for financing activities:	(82,783)	(214,474)
Effect of exchange rates on cash	(43)	185
Net (decrease) increase in cash and cash equivalents	(14,781)	2,608
Cash and cash equivalents, beginning of period	43,695	36,086
Cash and cash equivalents, end of period	28,914	38,694
SUPPLEMENTAL DISCLOSURES OF NON-CASH INVESTING AND FINANCING TRANSACTIONS:
Purchase of property and equipment by incurring current liabilities	3,067	1,650
Reduction of other current liabilities upon issuance of restricted share units	2,018	0
Extinguishment of Convertible Senior Notes through issuance of common stock	$ 86,428	$ 200,217