v3.21.1

Fair value measurement | 3 Months Ended
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Mar. 31, 2021
Fair value measurement |
Fair value measurement | 11. Fair value measurement The following table sets forth our financial assets and liabilities that are measured at fair value on a recurring basis: ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
At March 31, 2021 |  | Level 1 |  | Level 2 |  | Level 3 |  | Total
Assets: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Money market funds | ​ | $ | 28,463 | ​ | $ | — | ​ | $ | — | ​ | $ | 28,463
Total assets | ​ | $ | 28,463 | ​ | $ | — | ​ | $ | — | ​ | $ | 28,463
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
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
​ Our marketable securities utilize Level 1 and Level 2 inputs and consist primarily of corporate debt securities, which primarily include commercial paper and debt instruments including notes issued by foreign or domestic industrial and financial corporations and governments which pay in U.S. dollars and carry a rating of A or better. We have evaluated the various types of securities in our investment portfolio to determine an appropriate fair value hierarchy level based upon trading activity and the observability of market inputs. Due to variations in trading volumes and the lack of quoted market prices in active markets, our fixed maturity securities are classified as Level 2 securities. Our marketable securities are valued at amortized cost, which approximates fair value. The fair value of our fixed maturity marketable securities is derived through the use of a third-party pricing source using recent reported trades for identical or similar securities, making adjustments based upon available market observable data.

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- Definition The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
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