Marketable Securities (Details) $ in Thousands	Dec. 31, 2020 USD ($)
Marketable Securities
Amortized Cost	$ 157,640
Gross Unrealized Gains	14
Gross Unrealized Losses	(5)
Fair Value	157,649
Treasury securities
Marketable Securities
Amortized Cost	10,038
Gross Unrealized Gains	0
Gross Unrealized Losses	(2)
Fair Value	10,036
Corporate debt securities
Marketable Securities
Amortized Cost	127,003
Gross Unrealized Gains	13
Gross Unrealized Losses	(3)
Fair Value	127,013
Agency securities
Marketable Securities
Amortized Cost	20,599
Gross Unrealized Gains	1
Gross Unrealized Losses	0
Fair Value	$ 20,600

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 excluding accrued interest, before allowance for credit loss, 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
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
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Amount excluding accrued interest, 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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