CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Operating activities
Net loss	$ (34,358)	$ (19,698)
Adjustments to reconcile net loss to net cash provided by (used in) operating activities:
Depreciation and amortization	7,416	8,873
Stock-based compensation expense	3,186	3,176
Impairments		7,719
Restructuring and other charges	25,020	32,713
Gain on sale of assets	(3,955)	(467)
Deferred income taxes	(433)	(10,862)
Changes in operating assets and liabilities:
Trade receivables, net	11,024	(19,444)
Unbilled receivables	802	11,224
Inventories, net	(5,794)	(15,537)
Prepaids and other assets	4,962	(11,723)
Accounts payable and accrued expenses	5,202	(7,211)
Net cash provided by (used in) operating activities	13,072	(21,237)
Investing activities
Purchase of property, plant and equipment	(2,513)	(4,187)
Proceeds from sale of equipment	5,944	687
Net cash provided by (used in) investing activities	3,431	(3,500)
Financing activities
Repurchase of common shares		(25,000)
Other	(40)	(85)
Net cash used in financing activities	(40)	(25,085)
Effect of exchange rate changes on cash activities	(205)	(5,652)
Increase (decrease) in cash and cash equivalents	16,258	(55,474)
Cash and cash equivalents at beginning of period	345,955	398,946
Cash and cash equivalents at end of period	$ 362,213	$ 343,472