v3.20.1

Fair Value Measurements - Summary of Financial Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Financial Assets:
Marketable securities	$ 600,384	$ 176,674
Fair Value, Recurring
Financial Assets:
Total financial assets	781,797	765,436
Fair Value, Recurring | Money Market Funds
Financial Assets:
Cash equivalents	138,733	588,762
Fair Value, Recurring | Commercial Paper
Financial Assets:
Cash equivalents	27,478
Marketable securities	118,940	23,784
Fair Value, Recurring | U.S. Government Treasury Securities
Financial Assets:
Cash equivalents	12,000
Marketable securities	107,054	72,473
Fair Value, Recurring | Corporate Debt Securities
Financial Assets:
Marketable securities	319,499	80,417
Fair Value, Recurring | Certificates of Deposit
Financial Assets:
Cash equivalents	3,202
Marketable securities	39,919
Fair Value, Recurring | US Government Agencies
Financial Assets:
Marketable securities	14,972
Fair Value, Recurring | Level 1
Financial Assets:
Total financial assets	138,733	588,762
Fair Value, Recurring | Level 1 | Money Market Funds
Financial Assets:
Cash equivalents	138,733	588,762
Fair Value, Recurring | Level 2
Financial Assets:
Total financial assets	643,064	176,674
Fair Value, Recurring | Level 2 | Commercial Paper
Financial Assets:
Cash equivalents	27,478
Marketable securities	118,940	23,784
Fair Value, Recurring | Level 2 | U.S. Government Treasury Securities
Financial Assets:
Cash equivalents	12,000
Marketable securities	107,054	72,473
Fair Value, Recurring | Level 2 | Corporate Debt Securities
Financial Assets:
Marketable securities	319,499	$ 80,417
Fair Value, Recurring | Level 2 | Certificates of Deposit
Financial Assets:
Cash equivalents	3,202
Marketable securities	39,919
Fair Value, Recurring | Level 2 | US Government Agencies
Financial Assets:
Marketable securities	$ 14,972

X

- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
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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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=118942338&loc=SL82898722-210454

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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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