CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Cash flows from operating activities:
Net income (loss)		$ 322,052	$ (149,594)	$ (69,632)
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Depreciation and amortization		34,623	44,595	50,396
Stock-based compensation		55,153	17,725	23,587
Provision for inventory obsolescence and revaluation		(2,909)	12,373	0
Loss on hedge accounting de-designation and termination		721	1,235	0
Provision for bad debts		232	457	1,308
(Gain) Loss on the disposition of businesses, property, equipment and other assets		(350,846)	5,274	2,282
Provision for deferred income taxes and reserve adjustments		(11,679)	(1,206)	(3,354)
Impairment of goodwill and assets		1,676	55,484	1,728
Changes in operating accounts:
Accounts receivable		(11,912)	(6,052)	15,071
Inventories		7,866	(9,901)	18,447
Prepaid expenses and other current assets		(8,106)	(16,218)	9,150
Accounts payable		27,159	(6,653)	(16,846)
Deferred revenue and customer deposits		(3,325)	3,231	677
Accrued and other liabilities		(12,389)	28,286	(1,346)
All other operating activities		(169)	843	113
Net cash provided by (used in) operating activities		48,147	(20,121)	31,581
Cash flows from investing activities:
Purchases of property and equipment		(18,791)	(13,643)	(23,985)
Proceeds from sale of assets and businesses, net of cash		421,485	1,554	1,620
Business acquisitions, net of cash acquired		(139,685)	0	0
Other investing activities		(2,454)	356	(2,007)
Net cash provided by (used in) investing activities		260,555	(11,733)	(24,372)
Cash flows from financing activities:
Proceeds from revolving credit facilities		0	20,000	0
Payments on revolving credit facilities		0	(20,000)	0
Proceeds from borrowings		460,000	0	100,000
Debt issuance costs		(13,466)	0	0
Repayment of borrowings/long-term debt		(21,392)	(26,840)	(76,768)
Proceeds from issuance of common stock		0	24,702	0
Purchase of noncontrolling interests		(6,300)	(12,500)	(2,500)
Payments related to net-share settlement of stock-based compensation		(12,619)	(5,138)	(3,194)
Other financing activities		(423)	296	(1,338)
Net cash provided by (used in) financing activities		405,800	(19,480)	16,200
Effect of exchange rate changes on cash, cash equivalents and restricted cash		(9,243)	1,428	289
Net increase (decrease) in cash, cash equivalents and restricted cash		705,259	(49,906)	23,698
Cash, cash equivalents and restricted cash at the beginning of the year	[1]	84,711	134,617	110,919
Cash, cash equivalents and restricted cash at the end of the year	[1]	789,970	84,711	134,617
Supplemental cash flow information
Lease assets obtained in exchange for new lease liabilities (excludes adoption)		4,502	23,309	8,662
Cash interest payments		1,138	2,109	3,715
Cash income tax payments (receipts), net		4,709	3,706	10,722
Transfer of equipment from inventory to property and equipment, net	[2]	1,738	1,055	3,187
Transfer of equipment to inventory from property and equipment, net	[3]	0	0	32
Stock issued for acquisition		99,044	0	0
Noncash financing activity
Purchase of noncontrolling interest	[4]	$ 0	$ 0	$ (11,000)

[1] The amounts for cash and cash equivalents shown above include restricted cash of $313, $540 and $921 as of December 31, 2021, 2020 and 2019, respectively, which were included in Other assets, net, and $9,161 as of December 31, 2020, which was included in Current assets held for sale in the consolidated balance sheets.

[2] Inventory is transferred from inventory to property and equipment at cost when we require additional machines for training or demonstration or for placement into on demand manufacturing services locations.

[3] In general, an asset is transferred from Property and equipment, net, into inventory at its net book value when we have identified a potential sale for a used machine.

[4] Purchase of noncontrolling interest to be paid in installments over a four-year period recorded to Accrued and other liabilities and Other liabilities on the consolidated balance sheets.