Fair value measurements (Details) - Recurring - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Fair value measurements
Total Assets	$ 77,170	$ 104,056
Derivative liability, included in other long-term liabilities	16	331
Total Liabilities	16	331
Money market funds, included in cash and cash equivalents
Fair value measurements
Money market funds	76,973	103,859
Money market funds, included in restricted cash
Fair value measurements
Money market funds	197	197
Level 1
Fair value measurements
Total Assets	77,170	104,056
Level 1 \| Money market funds, included in cash and cash equivalents
Fair value measurements
Money market funds	76,973	103,859
Level 1 \| Money market funds, included in restricted cash
Fair value measurements
Money market funds	197	197
Level 3
Fair value measurements
Derivative liability, included in other long-term liabilities	16	331
Total Liabilities	$ 16	$ 331

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

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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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- Definition

Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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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Fair value of financial obligations, including, but not limited to, debt instruments, derivative liabilities, federal funds purchased and sold under agreements to repurchase, securities loaned or sold under agreements to repurchase, financial instruments sold not yet purchased, guarantees, line of credit, loans and notes payable, servicing liability, and trading liabilities.

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