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Marketable Securities (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Amortized Cost |  |
Amortized Cost | $ 150,593 | $ 53,128
Gross Unrealized Gains |  |
Gross Unrealized Gains | 5 | 26
Gross Unrealized Losses |  |
Gross Unrealized Losses | (12) | (3)
Fair Value |  |
Fair Value | 150,586 | 53,151
U.S. government and municipal obligations |  |
Amortized Cost |  |
Maturing in one year or less | 40,328 | 18,509
Amortized Cost | 40,328 | 18,509
Gross Unrealized Gains |  |
Maturing in one year or less | 3 | 13
Gross Unrealized Gains | 3 | 13
Gross Unrealized Losses |  |
Maturing in one year or less | (2) |
Gross Unrealized Losses | (2) |
Fair Value |  |
Maturing in one year or less | 40,329 | 18,522
Fair Value | 40,329 | 18,522
Corporate debt securities |  |
Amortized Cost |  |
Maturing in one year or less | 110,265 | 34,619
Amortized Cost | 110,265 | 34,619
Gross Unrealized Gains |  |
Maturing in one year or less | 2 | 13
Gross Unrealized Gains | 2 | 13
Gross Unrealized Losses |  |
Maturing in one year or less | (10) | (3)
Gross Unrealized Losses | (10) | (3)
Fair Value |  |
Maturing in one year or less | 110,257 | 34,629
Fair Value | $ 110,257 | $ 34,629

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