Investments - Schedule of Available-for-sale Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Debt and Equity Securities, FV-NI [Line Items]
Amortized Cost	$ 50,131	$ 47,415
Gross Unrealized Gains	88	39
Gross Unrealized Losses	(4)	(17)
Fair Value	50,215	47,437
Certificates of deposit
Debt and Equity Securities, FV-NI [Line Items]
Amortized Cost	6,838	5,646
Gross Unrealized Gains	19	17
Gross Unrealized Losses	0	0
Fair Value	6,857	5,663
U.S. Treasury securities
Debt and Equity Securities, FV-NI [Line Items]
Amortized Cost	13,435	12,564
Gross Unrealized Gains	49	16
Gross Unrealized Losses	0	(1)
Fair Value	13,484	12,579
U.S. Agency securities
Debt and Equity Securities, FV-NI [Line Items]
Amortized Cost	0	4,002
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	(4)
Fair Value	0	3,998
Commercial paper
Debt and Equity Securities, FV-NI [Line Items]
Amortized Cost	9,345	2,492
Gross Unrealized Gains	1	0
Gross Unrealized Losses	(1)	(1)
Fair Value	9,345	2,491
Corporate notes and bonds
Debt and Equity Securities, FV-NI [Line Items]
Amortized Cost	20,513	22,711
Gross Unrealized Gains	19	6
Gross Unrealized Losses	(3)	(11)
Fair Value	$ 20,529	$ 22,706

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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