v3.20.4

Fair value measurement (Tables) | 12 Months Ended
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Dec. 31, 2020
Fair value measurement |
Schedule of financial assets and liabilities that are measured at fair value on a recurring basis | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
At December 31, 2020 |  | Level 1 |  | Level 2 |  | Level 3 |  | Total
Assets: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Money market funds | ​ | $ | 20,825 | ​ | $ | — | ​ | $ | — | ​ | $ | 20,825
Marketable securities | ​ | ​ | — | ​ |  | 4,565 | ​ |  | — | ​ |  | 4,565
Total assets | ​ | $ | 20,825 | ​ | $ | 4,565 | ​ | $ | — | ​ | $ | 25,390
​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
At December 31, 2019 |  |  | Level 1 |  |  | Level 2 |  |  | Level 3 |  |  | Total
Assets: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Money market funds | ​ | $ | 32,843 | ​ | $ | 1,497 | ​ | $ | — | ​ | $ | 34,340
Marketable securities | ​ | ​ | 6,262 | ​ | ​ | 33,952 | ​ | ​ | — | ​ | ​ | 40,214
Total assets | ​ | $ | 39,105 | ​ | $ | 35,449 | ​ | $ | — | ​ | $ | 74,554
Schedule of reconciliation of the beginning and ending amounts related to the fair value of contingent consideration categorized as Level 3 | ​
​ | ​ | ​ | ​
Beginning balance, January 1, 2019 | ​ | $ | 961
Change in fair value | ​ | ​ | (961)
Balance, December 31, 2019 |  | $ | —

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- Definition Tabular disclosure of the fair value measurement of liabilities using significant unobservable inputs (Level 3), a reconciliation of the beginning and ending balances, separately presenting changes attributable to the following: (1) total gains or losses for the period (realized and unrealized), segregating those gains or losses included in earnings (or changes in net assets), and gains or losses recognized in other comprehensive income (loss) and a description of where those gains or losses included in earnings (or changes in net assets) are reported in the statement of income (or activities); (2) purchases, sales, issues, and settlements (each type disclosed separately); and (3) transfers in and transfers out of Level 3 (for example, transfers due to changes in the observability of significant inputs) by class of liability. + References 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 (c) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19279-110258 + Details
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- Definition Tabular disclosure of assets and liabilities, including [financial] instruments measured at fair value that are classified in stockholders' equity, if any, that are measured at fair value on a recurring basis. The disclosures contemplated herein include the fair value measurements at the reporting date by the level within the fair value hierarchy in which the fair value measurements in their entirety fall, segregating fair value measurements using quoted prices in active markets for identical assets (Level 1), significant other observable inputs (Level 2), and significant unobservable inputs (Level 3). + 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 (b) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
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