CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Cash flows from operating activities:
Net income (loss)	$ (13,124)	$ 9,284	$ (31,893)	$ 14,891	$ 19,808
Adjustments to reconcile net income (loss) to net cash used in operating activities:
Depreciation and amortization	2,734	2,188	7,584	6,677	9,150
Asset write-downs and impairment of field equipment	113	124	467	263	429
Share-based compensation	25,758	20,121	72,502	55,448	75,721
Foreign currency remeasurement loss (gain)	495	(79)	3,024	(549)	(699)
Decrease (increase) in accounts receivables	(3,726)	(7,678)	3,923	(33,556)	(30,354)
Amortization of discount (premium)	785	424	2,313	(654)	3,260
Decrease (increase) in inventories	3,818	(55)	4,185	(2,446)	(2,935)
Decrease (increase) in other long-term assets	1,367	(5,173)	4,383	(2,794)	(1,366)
Increase (decrease) in accounts payables and accrued expenses	8,126	9,908	10,622	7,974	25,470
Increase (decrease) in other long-term liabilities	(1,946)	1,905	(8,758)	413	664
Net cash provided by (used in) operating activities	24,400	30,969	68,352	45,667	99,148
Cash flows from investing activities:
Purchase of property, equipment and field equipment	(3,297)	(2,782)	(9,896)	(9,209)	(14,968)
Proceeds from maturity of short-term investments	350,000	150,000	958,000	150,000	150,000
Purchase of short-term investments	(44,000)	0	(593,848)	0	(607,879)
Net cash provided by (used in) investing activities	302,703	147,218	354,256	140,791	(472,847)
Cash flows from financing activities:
Proceeds from issuance of shares, net	0	0	2,371	1,667	3,370
Proceeds from long term debt, net	0	0	0	0	558,439
Repayment of long-term loan	(6)	(150,007)	(19)	(150,022)	(150,028)
Exercise of options and warrants	3,042	9,514	19,698	17,710	28,428
Net cash provided by (used in) financing activities	3,036	(140,493)	22,050	(130,645)	440,209
Effect of exchange rate changes on cash, cash equivalents and restricted cash	(34)	102	(139)	152	247
Increase (decrease) in cash, cash equivalents and restricted cash	330,105	37,796	444,519	55,965	66,757
Cash, cash equivalents and restricted cash at the beginning of the period	360,587	197,585	246,173	179,416	179,416
Cash, cash equivalents and restricted cash at the end of the period	690,692	235,381	690,692	235,381	246,173
Cash paid during the period for:
Income taxes paid (refunded), net	991	4,382	1,075	11,319	(3,261)
Interest paid	1	1,840	3	8,671	8,686
Non-cash activities:
Right-of-use assets obtained in exchange for lease liabilities	$ 1,023	$ 675	$ 1,972	$ 2,849	$ 5,617