Cash, Cash Equivalents and Investments - Summary of Cash Equivalents and Investments (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Debt Securities, Available-for-sale [Line Items]
Cash	$ 83,078	$ 100,094
Corporate bonds and commercial paper
Debt Securities, Available-for-sale [Line Items]
Investments, amortized cost	29,765	32,216
Gross Unrealized Gains	28	110
Gross Unrealized Losses	(41)	(1)
Investments, fair value	29,752	32,325
Cash
Debt Securities, Available-for-sale [Line Items]
Cash	65,900	85,600
Money market funds
Debt Securities, Available-for-sale [Line Items]
Cash equivalents, amortized cost	17,228	14,518
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Cash equivalents, fair value	$ 17,228	$ 14,518

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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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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