Cash and cash equivalents gross unrealized gains.

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Cash, cash equivalents and short term investments fair value disclosure.

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Cash, cash equivalents and short term investments gross unrealized gains.

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- Definition

Cash, cash equivalents and short term investments gross unrealized losses.

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Cash and cash equivalents and short term investments.

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Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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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.

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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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Cash includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the customer may deposit additional funds at any time and effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid Investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means 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. Short-term investments, exclusive of cash equivalents, generally consist of marketable securities intended to be sold within one year (or the normal operating cycle if longer) and may include trading securities, available-for-sale securities, or held-to-maturity securities (if maturing within one year), as applicable.

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Amount of 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, classified as other. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Cash, Cash Equivalents and Short-Term Investments - Schedule of Securities Classified as Cash, Cash Equivalents and Short-term Investments (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Cash Cash Equivalents And Short Term Investments [Line Items]
Cash and cash equivalents, Amortized Cost	$ 181,133	$ 78,768	$ 75,383	$ 74,598
Cash and cash equivalents, Amortized Cost	181,130
Cash and cash equivalents, Gross Unrealized Gains	3
Cash and cash equivalents, Fair Value	181,133	78,768
Short-term investments, Amortized Cost	66,362	89,359
Short-term investments, Gross Unrealized Gains	20
Short-term investments, Gross Unrealized Losses	(3)	(38)
Short-term investments, Fair Value	66,379	89,321
Cash equivalents and short-term investments, Amortized Cost	247,492	168,127
Cash equivalents and short-term investments, Gross Unrealized Gains	23
Cash equivalents and short-term investments, Gross Unrealized Losses	(3)	(38)
Cash equivalents and short-term investments, Fair Value	247,512	168,089
Cash [Member]
Cash Cash Equivalents And Short Term Investments [Line Items]
Cash and cash equivalents, Amortized Cost	3,124	3,733
Cash and cash equivalents, Fair Value	3,124	3,733
Money Market Funds [Member]
Cash Cash Equivalents And Short Term Investments [Line Items]
Cash and cash equivalents, Amortized Cost	147,208	73,238
Cash and cash equivalents, Fair Value	147,208	73,238
Corporate Bonds (Investments) [Member]
Cash Cash Equivalents And Short Term Investments [Line Items]
Cash and cash equivalents, Amortized Cost	11,441
Cash and cash equivalents, Fair Value	11,441
Commercial Paper (Cash Equivalents) [Member]
Cash Cash Equivalents And Short Term Investments [Line Items]
Cash and cash equivalents, Amortized Cost	19,357	1,797
Cash and cash equivalents, Gross Unrealized Gains	3
Cash and cash equivalents, Fair Value	19,360	1,797
U.S. Treasury Securities [Member]
Cash Cash Equivalents And Short Term Investments [Line Items]
Cash and cash equivalents, Amortized Cost		3,996
Cash and cash equivalents, Fair Value		3,996
Corporate Bonds (Investments) [Member]
Cash Cash Equivalents And Short Term Investments [Line Items]
Short-term investments, Amortized Cost	21,690	34,611
Short-term investments, Gross Unrealized Gains	6
Short-term investments, Gross Unrealized Losses	(3)	(21)
Short-term investments, Fair Value	21,693	34,590
Commercial Paper (Investments) [Member]
Cash Cash Equivalents And Short Term Investments [Line Items]
Short-term investments, Amortized Cost	36,667	41,371
Short-term investments, Gross Unrealized Gains	14
Short-term investments, Gross Unrealized Losses		(14)
Short-term investments, Fair Value	36,681	41,357
Asset-Backed Securities [Member]
Cash Cash Equivalents And Short Term Investments [Line Items]
Short-term investments, Amortized Cost	8,005	9,381
Short-term investments, Gross Unrealized Losses		(3)
Short-term investments, Fair Value	$ 8,005	$ 9,378