CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 9,656	$ 32,828
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	68,507	50,436
Loss on sales and/or abandonment of property and equipment	637	425
Amortization of right-of-use operating lease assets	9,226
Write-off of patents and intangible assets	3,492	744
Acquired in-process research and development	525	382
Amortization of deferred credits	(104)	(106)
Amortization of long-term debt issuance costs	570	603
Stock-based compensation expense	6,915	4,494
Changes in operating assets and liabilities, net of effects from acquisitions:
Trade receivables	(6,786)	(25,482)
Other receivables	72	255
Inventories	(19,302)	(19,375)
Prepaid expenses and other current assets	(3,859)	(2,719)
Prepaid income taxes		(120)
Income tax refund receivables	(8,680)	134
Other assets	(3,832)	(1,370)
Trade payables	(3,775)	15,936
Accrued expenses	66	7,707
Income taxes payable	(928)	(1,528)
Deferred compensation payable	2,276	994
Operating lease liabilities	(8,956)
Other long-term obligations	5,184	(1,381)
Total adjustments	41,248	30,029
Net cash provided by operating activities	50,904	62,857
Capital expenditures for:
Property and equipment	(58,104)	(47,024)
Intangible assets	(2,560)	(2,234)
Proceeds from the sale of property and equipment	262	7
Issuance of note receivable	0	(10,750)
Cash paid in acquisitions, net of cash acquired	(53,512)	(122,770)
Net cash used in investing activities	(113,914)	(182,771)
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from issuance of common stock	5,863	213,276
Offering costs		(366)
Proceeds from issuance of long-term debt	194,477	380,825
Payments on long-term debt	(149,477)	(450,575)
Long-term debt issuance costs	(1,479)
Contingent payments related to acquisitions	(15,684)	(184)
Payment of taxes related to an exchange of common stock		(2,616)
Net cash provided by financing activities	33,700	140,360
EFFECT OF EXCHANGE RATES ON CASH	(734)	(827)
NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	(30,044)	19,619
CASH AND CASH EQUIVALENTS:
Beginning of period	67,359	32,336
End of period	37,315	51,955
SUPPLEMENTAL DISCLOSURES OF CASH FLOW INFORMATION
Interest (net of capitalized interest of $896 and $468, respectively)	9,319	8,018
Income taxes	10,071	6,069
SUPPLEMENTAL DISCLOSURES OF NON-CASH INVESTING AND FINANCING ACTIVITIES
Property and equipment purchases in accounts payable	7,481	3,058
Acquisition purchases in accrued expenses and other long-term obligations	9,583	0
Merit common stock surrendered (3 and 43 shares, respectively) in exchange for exercise of stock options	93	$ 2,262
Right-of-use operating lease assets obtained in exchange for operating lease liabilities	$ 7,431