v3.19.2

Fair value measurement (Details) - Recurring basis - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Assets:
Money market accounts	$ 22,983	$ 137,723
Marketable securities	42,799
Total assets	65,782	137,723
Liabilities:
Contingent consideration	961	961
Total liabilities	961	961
Level 1
Assets:
Money market accounts	22,983	137,723
Marketable securities	6,987
Total assets	29,970	137,723
Level 2
Assets:
Marketable securities	35,812
Total assets	35,812
Level 3
Liabilities:
Contingent consideration	961	961
Total liabilities	$ 961	$ 961

X

- Definition

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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- 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

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Amount of liability recognized arising from contingent consideration in a business combination.

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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 of financial and nonfinancial obligations.

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