Marketable Securities - Summary of Investments (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Marketable securities available-for-sale
Amortization Cost	$ 64,980	$ 121,103
Gross Unrealized Gains	234	39
Gross Unrealized Losses		(2)
Estimated Fair Value	65,214	121,140
U.S. Treasury obligations
Marketable securities available-for-sale
Amortization Cost	64,980	121,103
Gross Unrealized Gains	234	39
Gross Unrealized Losses		(2)
Estimated Fair Value	$ 65,214	$ 121,140

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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+ References

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