Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 9,220	$ 18,452
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	46,673	48,340
Income tax, non-cash changes	1,582	6,968
Stock-based compensation	1,917	1,712
Amortization of debt issuance costs	2,456	1,928
Other non-cash items	(1,630)	1,921
Accounts receivable	(22,538)	(22,087)
Inventories	(2,660)	(16,240)
Other assets and liabilities	12,574	(7,635)
Accounts payable	10,655	(2,288)
Income taxes	11,382	(270)
NET CASH PROVIDED BY OPERATING ACTIVITIES	69,631	30,801
CASH FLOWS FROM INVESTING ACTIVITIES:
Additions to property, plant and equipment	(28,665)	(38,020)
Other investing activities	9,631	(118)
NET CASH USED IN INVESTING ACTIVITIES	(19,034)	(38,138)
CASH FLOWS FROM FINANCING ACTIVITIES:
Debt repayment	(24,183)	(3,614)
Cash dividends paid	(12,910)	(15,547)
Purchase of non-controlling redeemable shares	(1,411)
Payments related to tax withholdings for stock-based compensation	(108)	(605)
Proceeds from the exercise of stock options		68
Proceeds from borrowings on revolving credit facility	43,800	85,400
Repayments of borrowings on revolving credit facility	(43,800)	(85,400)
Other financing activities	(654)
NET CASH USED IN FINANCING ACTIVITIES	(39,266)	(19,698)
Effect of exchange rate changes on cash	(1,872)	(258)
Net increase (decrease) in cash and cash equivalents	9,459	(27,293)
Cash and cash equivalents at the beginning of the period	47,464	46,360
Cash and cash equivalents at the end of the period	$ 56,923	$ 19,067