Investments in marketable securities - Marketable Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Cash and Cash Equivalents
Cash and Cash Equivalents [Abstract]
Cash Equivalents, at Carrying Value	$ 35,736	$ 23,218
Cash Equivalents, Fair Value Disclosure	35,737	23,218
Debt Securities, Available-for-Sale [Abstract]
Gross Unrealized Gain	1
Gross Unrealized Loss	0
Short Term Marketable Securities
Debt Securities, Available-for-Sale [Abstract]
Amortized Cost	107,409	117,674
Gross Unrealized Gain	4	0
Gross Unrealized Loss	(1,259)	(1,537)
Fair Value	106,154	116,137
Long Term Marketable Securities
Debt Securities, Available-for-Sale [Abstract]
Amortized Cost	31,985	38,129
Gross Unrealized Gain	5	0
Gross Unrealized Loss	(200)	(766)
Fair Value	31,790	37,363
US government money market fund \| Cash and Cash Equivalents
Cash and Cash Equivalents [Abstract]
Money Market Funds, at Carrying Value	31,745	23,218
US treasury bills \| Cash and Cash Equivalents
Debt Securities, Available-for-Sale [Abstract]
Amortized Cost	3,991
Gross Unrealized Gain	1
Gross Unrealized Loss	0
Fair Value	3,992
US treasury bills \| Short Term Marketable Securities
Debt Securities, Available-for-Sale [Abstract]
Amortized Cost		8,483
Gross Unrealized Gain		0
Gross Unrealized Loss		(16)
Fair Value		8,467
US treasury bills \| Long Term Marketable Securities
Debt Securities, Available-for-Sale [Abstract]
Amortized Cost		25,433
Gross Unrealized Gain		0
Gross Unrealized Loss		(336)
Fair Value		25,097
US government agency bonds \| Short Term Marketable Securities
Debt Securities, Available-for-Sale [Abstract]
Amortized Cost	25,448	26,686
Gross Unrealized Gain	4	0
Gross Unrealized Loss	(343)	(424)
Fair Value	25,109	26,262
US government agency bonds \| Long Term Marketable Securities
Debt Securities, Available-for-Sale [Abstract]
Amortized Cost	7,193	3,724
Gross Unrealized Gain	4	0
Gross Unrealized Loss	0	(130)
Fair Value	7,197	3,594
US corporate bonds \| Short Term Marketable Securities
Debt Securities, Available-for-Sale [Abstract]
Amortized Cost	37,075	27,144
Gross Unrealized Gain	0	0
Gross Unrealized Loss	(300)	(303)
Fair Value	36,775	26,841
US corporate bonds \| Long Term Marketable Securities
Debt Securities, Available-for-Sale [Abstract]
Amortized Cost	24,792
Gross Unrealized Gain	0
Gross Unrealized Loss	(200)
Fair Value	24,593
US government bonds \| Short Term Marketable Securities
Debt Securities, Available-for-Sale [Abstract]
Amortized Cost	44,886	55,361
Gross Unrealized Gain	0	0
Gross Unrealized Loss	(616)	(794)
Fair Value	$ 44,270	54,567
US government bonds \| Long Term Marketable Securities
Debt Securities, Available-for-Sale [Abstract]
Amortized Cost		8,972
Gross Unrealized Gain		0
Gross Unrealized Loss		(300)
Fair Value		$ 8,672

Cash Equivalents, Fair Value Disclosure

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Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
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-Name Accounting Standards Codification
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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
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Amount of short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Investment in short-term money-market instruments (such as commercial paper, banker's acceptances, repurchase agreements, government securities, certificates of deposit, and so forth) which are highly liquid (that is, readily convertible to known amounts of cash) and so near their maturity that they present an insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify as cash equivalents by definition. Original maturity means an original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months.

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