Investments (Details 2) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Debt Securities, Held-to-maturity	$ 24,005
Money Market Funds [Member]
Debt Securities, Held-to-maturity	6,979	$ 29,876
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Gross Unrealized Fair Value	6,979	29,876
Commercial Paper [Member]
Debt Securities, Held-to-maturity	28,337	2,248
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(37)	0
Gross Unrealized Fair Value	28,300	2,248
Bonds [Member]
Debt Securities, Held-to-maturity	24,005	40,236
Gross Unrealized Gains	2	97
Gross Unrealized Losses	(275)	(37)
Gross Unrealized Fair Value	23,732	40,296
Mutual funds (available for sale) [Member]
Debt Securities, Held-to-maturity	476	558
Gross Unrealized Gains	0	1
Gross Unrealized Losses	(91)	0
Gross Unrealized Fair Value	385	559
Equity investments [Member]
Debt Securities, Held-to-maturity	6,054	5,675
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(983)	(207)
Gross Unrealized Fair Value	$ 5,071	$ 5,468

Amount, before allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity).

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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