Fair Value Measurements and Available for Sale Investments - Schedule of Unrealized Loss and Fair Values in a Loss Position (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Debt Securities, Available-for-sale [Line Items]
Less than 12 Months, Fair Value	$ 39,317	$ 23,594
Less than 12 Months, Gross Unrealized Losses	(14)	(6)
12 Months or Greater, Fair Value	0	0
12 Months or Greater, Gross Unrealized Losses	0	0
Fair Value	39,317	23,594
Gross Unrealized Losses	(14)	(6)
Agency securities
Debt Securities, Available-for-sale [Line Items]
Less than 12 Months, Fair Value	9,998
Less than 12 Months, Gross Unrealized Losses	(1)
12 Months or Greater, Fair Value	0
12 Months or Greater, Gross Unrealized Losses	0
Fair Value	9,998
Gross Unrealized Losses	(1)
Commercial and corporate obligations
Debt Securities, Available-for-sale [Line Items]
Less than 12 Months, Fair Value	4,096	5,986
Less than 12 Months, Gross Unrealized Losses	(3)	(4)
12 Months or Greater, Fair Value	0	0
12 Months or Greater, Gross Unrealized Losses	0	0
Fair Value	4,096	5,986
Gross Unrealized Losses	(3)	(4)
U.S. Treasury securities
Debt Securities, Available-for-sale [Line Items]
Less than 12 Months, Fair Value	25,223	17,608
Less than 12 Months, Gross Unrealized Losses	(10)	(2)
12 Months or Greater, Fair Value	0	0
12 Months or Greater, Gross Unrealized Losses	0	0
Fair Value	25,223	17,608
Gross Unrealized Losses	$ (10)	$ (2)

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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