Cash and cash equivalents and marketable securities (Details) - USD ($) $ in Thousands |
3 Months Ended | 6 Months Ended | |||
|---|---|---|---|---|---|
Jun. 30, 2019 |
Jun. 30, 2018 |
Jun. 30, 2019 |
Jun. 30, 2018 |
Dec. 31, 2018 |
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| Cash and cash equivalents: | |||||
| Cash | $ 4,398 | $ 4,398 | $ 11,689 | ||
| Money market accounts | 22,983 | 22,983 | 137,723 | ||
| Total cash and cash equivalents | 27,381 | 27,381 | 149,412 | ||
| Short-term marketable securities-available-for-sale: | |||||
| Marketable securities | 42,799 | 42,799 | 0 | ||
| Total short-term marketable securities | 42,799 | 42,799 | $ 0 | ||
| Interest income | $ 540 | $ 11 | $ 1,254 | $ 19 | |
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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), classified as current. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount 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. Excludes cash and cash equivalents within disposal group and discontinued operation. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount 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. Excludes cash and cash equivalents within disposal group and discontinued operation. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- References No definition available.
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- Definition Amount before accretion (amortization) of purchase discount (premium) of interest income on nonoperating securities. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- References No definition available.
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- Definition Amount of investment in marketable security, classified as current. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Investment in short-term money-market instruments (such as commercial paper, banker's acceptances, repurchase agreements, government securities, certificates of deposit, and so forth) which are highly liquid (that is, readily convertible to known amounts of cash) and so near their maturity that they present an insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify as cash equivalents by definition. Original maturity means an original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months. No definition available.
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