Available-for-Sale-Securities - Schedule of Available-for-Sale Securities Reconciliation (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Debt Securities, Available-for-sale [Line Items]
Cost	$ 37,796	$ 22,766
Gross Unrealized Gains	0	3
Gross Unrealized Losses	(12)	(1)
Estimated Fair Value	37,784	22,768
Corporate debt securities
Debt Securities, Available-for-sale [Line Items]
Cost	13,506	11,673
Gross Unrealized Gains	0	3
Gross Unrealized Losses	(11)	(1)
Estimated Fair Value	13,495	11,675
Money market funds
Debt Securities, Available-for-sale [Line Items]
Cost	15,481	11,093
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	15,481	11,093
Municipal debt securities
Debt Securities, Available-for-sale [Line Items]
Cost	8,613	0
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(1)	0
Estimated Fair Value	8,612	0
Sovereign government securities
Debt Securities, Available-for-sale [Line Items]
Cost	196	0
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	$ 196	$ 0

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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Amortized cost 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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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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