Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Cash flows from operating activities:
Net income (loss)	$ (22,668)	$ 10,195
Depreciation and amortization	135,835	142,509
Other operating activities and non-cash items	15,928	(4,734)
Changes in assets and liabilities	(77,038)	(339)
Net cash provided by operating activities	52,057	147,631
Cash flows from investing activities:
Payments for property, plant and equipment	(203,216)	(230,603)
Proceeds from sale of property, plant and equipment	180	342
Proceeds from insurance recovery for property, plant and equipment	1,538	0
Other investing activities	(569)	656
Net cash used in investing activities	(202,067)	(229,605)
Cash flows from financing activities:
Proceeds from short-term debt	29,781	0
Payments of short-term debt	(10,588)	(17,352)
Proceeds from issuance of long-term debt	572,375	0
Payments of long-term debt	(63,636)	(6,220)
Payments of finance lease obligations	(1,376)	(808)
Other financing activities	(2,848)	455
Net cash provided by (used in) financing activities	523,708	(23,925)
Effect of exchange rate fluctuations on cash, cash equivalents and restricted cash	(829)	3,892
Net increase (decrease) in cash, cash equivalents and restricted cash	372,869	(102,007)
Cash, cash equivalents and restricted cash, beginning of period	688,051	602,851
Cash, cash equivalents and restricted cash, end of period	1,060,920	500,844
Non-cash investing and financing activities:
Property, plant and equipment included in capital expenditures payable	124,547	224,037
Right of use assets acquired through finance lease liabilities	92	923
Right of use assets acquired through operating lease liabilities	$ 7,328	$ 0