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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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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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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Amount of transfers of assets measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

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Amount of transfers of assets measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

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Fair Value Measurements - (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020	Mar. 31, 2020
Fair value of the Company’s financial assets
Marketable securities	$ 231,709	$ 250,676
Assets transferred from level 1 to level 2	0		$ 0
Assets transferred from level 2 to level 1	0		$ 0
Carrying Amount
Fair value of the Company’s financial assets
Total financial assets	250,894	261,831
Fair Value \| Quoted Prices in Active Markets (Level 1)
Fair value of the Company’s financial assets
Total financial assets	19,185	11,155
Fair Value \| Significant Other Observable Inputs (Level 2)
Fair value of the Company’s financial assets
Total financial assets	231,709	250,676
Money market funds (cash equivalents) \| Carrying Amount
Fair value of the Company’s financial assets
Money market funds (cash equivalents)	19,185	11,155
Money market funds (cash equivalents) \| Fair Value \| Quoted Prices in Active Markets (Level 1)
Fair value of the Company’s financial assets
Money market funds (cash equivalents)	19,185	11,155
Corporate bonds \| Carrying Amount
Fair value of the Company’s financial assets
Marketable securities	231,709	243,679
Corporate bonds \| Fair Value \| Significant Other Observable Inputs (Level 2)
Fair value of the Company’s financial assets
Marketable securities	$ 231,709	243,679
Commercial Paper \| Carrying Amount
Fair value of the Company’s financial assets
Marketable securities		6,997
Commercial Paper \| Fair Value \| Significant Other Observable Inputs (Level 2)
Fair value of the Company’s financial assets
Marketable securities		$ 6,997