Marketable Securities - Summary of Investments (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Marketable securities available-for-sale
Amortization Cost	$ 25,999	$ 121,103
Gross Unrealized Gains	49	39
Gross Unrealized Losses		(2)
Estimated Fair Value	26,048	121,140
U.S. Treasury obligations
Marketable securities available-for-sale
Amortization Cost	25,999	121,103
Gross Unrealized Gains	49	39
Gross Unrealized Losses		(2)
Estimated Fair Value	$ 26,048	$ 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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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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