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)	$ (58,351)	$ 19,808	$ (7,230)
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Depreciation and amortization	10,251	9,150	8,460
Accrued interest	(94)	0	0
Asset write-downs and impairment of field equipment	649	429	398
Share-based compensation	94,900	75,721	52,416
Foreign currency remeasurement loss (gain)	3,231	(699)	(917)
Decrease (increase) in accounts receivables	5,270	(30,354)	(36,496)
Amortization of discount (premium)	3,101	3,260	(2,176)
Decrease (increase) in inventories	2,483	(2,935)	(1,159)
Decrease (increase) in other long-term assets	4,519	(1,366)	3,446
Increase (decrease) in accounts payables and accrued expenses	27,777	25,470	16,883
Increase (decrease) in other long-term liabilities	(10,980)	664	(7,006)
Net cash provided by (used in) operating activities	82,756	99,148	26,620
Cash flows from investing activities:
Purchase of property, equipment and field equipment	(24,170)	(14,968)	(10,485)
Proceeds from maturity of short-term investments	958,000	150,000	420,661
Purchase of short-term investments	(1,078,664)	(607,879)	(461,843)
Net cash provided by (used in) investing activities	(144,834)	(472,847)	(51,667)
Cash flows from financing activities:
Proceeds from issuance of shares, net	4,546	3,370	2,467
Proceeds from convertible note, net	0	558,439	0
Repayment of long-term debt	(26)	(150,028)	(31)
Exercise of options	21,182	28,428	59,245
Net cash provided by (used in) financing activities	25,702	440,209	61,681
Effect of exchange rate changes on cash, cash equivalents and restricted cash	(188)	247	26
Increase (decrease) in cash, cash equivalents and restricted cash	(36,564)	66,757	36,660
Cash, cash equivalents and restricted cash at the beginning of the year	246,173	179,416	142,756
Cash, cash equivalents and restricted cash at the end of the year	209,609	246,173	179,416
Cash paid during the year for:
Income taxes paid (refunded), net	3,110	(3,261)	11,241
Interest paid	101	8,686	13,699
Non-cash activities:
Right-of-use assets obtained in exchange for lease liabilities	$ 5,387	$ 5,617	$ 22,943