CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Operating activities
Net loss	$ (19,514)	$ (5,679)
Adjustments to reconcile net loss to net cash provided by (used in) operating activities:
Depreciation and amortization	24,721	25,155
Release of contingent consideration		(2,001)
Stock-based compensation expense	9,461	15,746
Impairments	7,719
Restructuring and other charges	34,902	162
Gain on sale of assets	(538)	(1,483)
Deferred income taxes	(2,116)	(534)
Changes in operating assets and liabilities:
Trade receivables, net	8,705	7,727
Unbilled receivables	(4,815)	(43,193)
Inventories, net	(38,475)	(15,624)
Prepaids and other assets	(23,185)	12,744
Accounts payable and accrued expenses	(1,169)	13,667
Other, net	2	(63)
Net cash provided by (used in) operating activities	(4,302)	6,624
Investing activities
Purchase of property, plant and equipment	(10,243)	(8,620)
Proceeds from sale of equipment	3,646	2,401
Net cash used in investing activities	(6,597)	(6,219)
Financing activities
Repurchase of common shares	(25,000)	(5,365)
Proceeds from exercise of stock options		2,327
Other	(176)	(239)
Net cash used in financing activities	(25,176)	(3,277)
Effect of exchange rate changes on cash activities	(3,700)	(2,126)
Decrease in cash and cash equivalents	(39,775)	(4,998)
Cash and cash equivalents at beginning of period	398,946	418,100
Cash and cash equivalents at end of period	$ 359,171	$ 413,102