Investments - - Carrying value and amortized cost of available-for-sale debt securities (Details) $ in Thousands	9 Months Ended
Sep. 30, 2022 USD ($)
Minimum
Investment securities
Non current investment maturity term	1 year
Maximum
Investment securities
Non current investment maturity term	2 years
Short-term
Investment securities
Amortized cost	$ 46,548
Gross Unrealized Gains	5
Gross Unrealized Losses	(133)
Fair Value	46,420
Short-term commercial paper
Investment securities
Amortized cost	12,089
Gross Unrealized Gains	1
Gross Unrealized Losses	(35)
Fair Value	12,055
Short-term corporate debt securities
Investment securities
Amortized cost	30,077
Gross Unrealized Gains	4
Gross Unrealized Losses	(80)
Fair Value	30,001
Short-term U.S. government securities
Investment securities
Amortized cost	4,382
Gross Unrealized Losses	(18)
Fair Value	4,364
Long-term
Investment securities
Amortized cost	8,330
Gross Unrealized Gains	3
Gross Unrealized Losses	(53)
Fair Value	8,280
Long-term corporate debt securities
Investment securities
Amortized cost	8,074
Gross Unrealized Gains	3
Gross Unrealized Losses	(50)
Fair Value	8,027
Long-term U.S. government securities
Investment securities
Amortized cost	256
Gross Unrealized Losses	(3)
Fair Value	$ 253

Maturity term of non current investments.

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- Definition

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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27161-111563

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- Definition

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27161-111563

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- Definition

Amortized cost of 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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27161-111563

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454

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- Definition

Amount of 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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(6))
-URI https://asc.fasb.org/extlink&oid=126897435&loc=d3e534808-122878

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
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-Section 45
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-URI https://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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-URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27161-111563

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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