Available-for-Sale-Securities - Schedule of Available-for-Sale Securities Reconciliation (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Debt Securities, Available-for-sale [Line Items]
Cost	$ 17,037	$ 22,766
Gross Unrealized Gains	0	3
Gross Unrealized Losses	0	(1)
Estimated Fair Value	17,037	22,768
Corporate debt securities
Debt Securities, Available-for-sale [Line Items]
Cost	0	11,673
Gross Unrealized Gains	0	3
Gross Unrealized Losses	0	(1)
Estimated Fair Value	0	11,675
Money market funds
Debt Securities, Available-for-sale [Line Items]
Cost	17,037	11,093
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	$ 17,037	$ 11,093

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).

+ References

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-Publisher FASB
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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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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