Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Operating activities:
Net loss	$ (35,241)	$ (16,983)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	18,444	19,467
Deferred income taxes	(3,656)	(5,113)
Loss (gain) on asset dispositions	51	879
Equity in (income) loss of unconsolidated affiliate, net	(1,361)	37
Inventory valuation reserves	741	1,042
Changes in operating assets and liabilities	(11,877)	(761)
Net cash used in operating activities	(32,899)	(1,432)
Investing activities:
Purchase of property and equipment	(6,947)	(6,665)
Proceeds from asset dispositions	12	842
Purchase of short-term investments	(139,616)	(134,319)
Proceeds from sale of short-term investments	80,512	136,259
Refund of Deposit on Aircraft	503	0
Loan to unconsolidated affiliate		(274)
Net cash used in investing activities	(65,536)	(4,157)
Financing activities:
Debt issuance cost	(5,668)	0
Proceeds from line of credit	0	33,750
Payments on line of credit	0	(29,500)
Proceeds from Term Loan	70,000	0
Net cash provided by financing activities	64,332	4,250
Effect of exchange rate changes on cash	(864)	0
Decrease in cash, cash equivalents and restricted cash	(34,967)	(1,339)
Cash, cash equivalents and restricted cash at the beginning of period	58,564	8,770
Cash, cash equivalents and restricted cash at end of period	23,597	7,431
Cash paid during the period for:
Reorganization items, net	1,600	0
Interest	2,058	14,328
Income taxes	655	320
Noncash investing activities:
Other current liabilities and accrued payables related to purchase of property and equipment	$ 73	$ 82