Cash and Cash Equivalents and Investments (Details 1) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Cash and Cash Equivalents
Fair Value
Amortized Cost	$ 59,520	$ 64,066
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	1
Estimated Fair Value	59,520	64,065
U.S. Treasury Securities
Fair Value
Amortized Cost	12,486	7,562
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(26)	(1)
Estimated Fair Value	12,460	7,561
Total Short-term Investments
Fair Value
Amortized Cost	27,019	22,687
Gross Unrealized Gains	4	0
Gross Unrealized Losses	(41)	(9)
Estimated Fair Value	26,982	22,678
Total Cash and Cash Equivalents and Investments
Fair Value
Amortized Cost	86,539	86,753
Gross Unrealized Gains	4	0
Gross Unrealized Losses	(41)	(10)
Estimated Fair Value	86,502	86,743
Corporate Debt Securities
Fair Value
Amortized Cost	14,533	15,125
Gross Unrealized Gains	4	0
Gross Unrealized Losses	(15)	(8)
Estimated Fair Value	$ 14,522	$ 15,117

Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27161-111563

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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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