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Cash Equivalents and Investments - Additional Information (Detail) - USD ($) $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2019 | Dec. 31, 2018
Maximum [Member] |  |
Cash Equivalents And Investments [Line Items] |  |
Long Term Investments Maturity Period | 5 years |
Short Term Investment Maturity Period | 1 year |
Minimum [Member] |  |
Cash Equivalents And Investments [Line Items] |  |
Long Term Investments Maturity Period | 1 year |
Cash Equivalents [Member] |  |
Cash Equivalents And Investments [Line Items] |  |
Cash equivalents | $ 2.5 | $ 0.5

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- Definition Long term investments maturity period. + References No definition available. + Details
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- Definition Short term investment maturity period. + References No definition available. + Details
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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. + References No definition available. + Details
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- Details
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