Marketable Investments - Summary of Company's marketable investments (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Debt Securities, Available-for-sale [Line Items]
Amortized cost	$ 20,234	$ 18,542
Gross Unrealized Gains	1	0
Gross Unrealized Losses	(232)	(33)
Market value	20,003	18,509
Corporate obligations
Debt Securities, Available-for-sale [Line Items]
Amortized cost	19,234	18,542
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(232)	(33)
Market value	19,002	$ 18,509
Federal agency obligations
Debt Securities, Available-for-sale [Line Items]
Amortized cost	1,000
Gross Unrealized Gains	1
Gross Unrealized Losses	0
Market value	$ 1,001

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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