Basis of presentation and summary of significant accounting policies - Fair Value (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Servicing Assets at Fair Value [Line Items]
Gross Unrealized Losses	$ (27)
Money market funds
Servicing Assets at Fair Value [Line Items]
Cash and Cash Equivalents, Fair Value Disclosure	33,767	$ 140,856
U.S. treasury securities
Servicing Assets at Fair Value [Line Items]
Gross Unrealized Losses	(27)
Fair Value, Recurring
Servicing Assets at Fair Value [Line Items]
Total financial assets	95,737	140,856
Fair Value, Recurring \| Money market funds
Servicing Assets at Fair Value [Line Items]
Cash and Cash Equivalents, Fair Value Disclosure	33,767	140,856
Fair Value, Recurring \| Level 1
Servicing Assets at Fair Value [Line Items]
Total financial assets	95,737	140,856
Fair Value, Recurring \| Level 1 \| Money market funds
Servicing Assets at Fair Value [Line Items]
Cash and Cash Equivalents, Fair Value Disclosure	33,767	140,856
Fair Value, Recurring \| Level 2
Servicing Assets at Fair Value [Line Items]
Total financial assets	0	0
Fair Value, Recurring \| Level 2 \| Money market funds
Servicing Assets at Fair Value [Line Items]
Cash and Cash Equivalents, Fair Value Disclosure	0	0
Fair Value, Recurring \| Level 3
Servicing Assets at Fair Value [Line Items]
Total financial assets	0	0
Fair Value, Recurring \| Level 3 \| Money market funds
Servicing Assets at Fair Value [Line Items]
Cash and Cash Equivalents, Fair Value Disclosure	0	0
Fair Value, Recurring \| U.S. treasury securities
Servicing Assets at Fair Value [Line Items]
U.S. treasury securities	61,970	0
Fair Value, Recurring \| U.S. treasury securities \| Level 1
Servicing Assets at Fair Value [Line Items]
U.S. treasury securities	61,970	0
Fair Value, Recurring \| U.S. treasury securities \| Level 2
Servicing Assets at Fair Value [Line Items]
U.S. treasury securities	0	0
Fair Value, Recurring \| U.S. treasury securities \| Level 3
Servicing Assets at Fair Value [Line Items]
U.S. treasury securities	$ 0	$ 0

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258

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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

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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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes 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.

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Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258

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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.

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