CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
Operating Activities
Net income	$ 106,561	$ 75,397
Adjustments to reconcile net income to net cash provided by operating activities, net of effects of acquisitions
Depreciation and amortization	81,302	76,868
Share-based compensation expense	15,364	15,975
Other	(206)	(615)
Changes in operating assets:
Change in accounts receivable	(29,868)	(28,596)
Change in inventory	(9,062)	(5,378)
Change in other operating assets	(3,475)	(11,177)
Changes in operating liabilities:
Change in accrued liabilities	10,206	9,070
Change in income tax payable (refundable)	9,853	(2,388)
Change in other operating liabilities	(2,970)	(5,228)
Net cash flows provided by operating activities	177,705	123,928
Cash flows from investing activities
Acquisitions, net of cash received	(33,029)	(41)
Purchases of property, plant and equipment	(76,128)	(72,159)
Purchases of short-term investments	(15,921)	(13,959)
Proceeds from maturity of short-term investments	15,332	10,831
Other	(430)	1,235
Net cash and cash equivalents used in investing activities	(110,176)	(74,093)
Cash flows from financing activities
Advances on lines of credit and short-term debt	9,954	9,151
Repayments of line of credit and short-term debt	(3,067)
Taxes paid related to net share settlement	(4,383)	(11,056)
Proceeds from long-term debt	278,237	304,656
Repayments of long-term debt	(372,976)	(408,863)
Net proceeds from issuance of common stock	7,208	4,861
Repayment of and proceeds from finance lease obligation	(912)	1,489
Dividend distribution to noncontrolling interests	(2,577)	(2,694)
Capital contribution from noncontrolling interest		5,263
Other	1,524	(764)
Net cash and cash equivalents used in financing activities	(86,992)	(97,957)
Effect of exchange rate changes on cash and cash equivalents	(2,614)	(6,039)
Change in cash and cash equivalents, including restricted cash	(22,077)	(54,161)
Cash and cash equivalents, beginning of period, including restricted cash	241,833	205,262
Cash and cash equivalents, end of period, including restricted cash	219,756	151,101
Supplemental Cash Flow Information
Interest paid during the period	5,781	7,661
Taxes paid during the period	24,422	29,435
Non-cash investing and financing activities:
(Increase) decrease in accounts payable related to the purchase of property, plant and equipment	$ (1,263)	$ 8,093