Short-term Investment Securities (Details) - USD ($)	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
Debt Securities, Available-for-sale [Line Items]
Short-term investment securities	$ 108,357,000		$ 107,115,000
Realized gain (loss) on available-for-sale securities	0	$ 0
Accumulated other comprehensive loss	390,000		596,000
Debt Securities, Available For Sale
Debt Securities, Available-for-sale [Line Items]
Short-term investment securities	$ 108,400,000		107,100,000
Weighted-average fixed rate	3.80%	0.20%
Unrealized gain (loss) on investment securities, net of deferred taxes	$ 184,000	$ (262,000)
Accumulated other comprehensive loss	$ (82,000)		$ (267,000)

Interest Income, Weighted-Average Fixed Rate

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Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

+ References

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- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), classified as current.

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Amount of realized gain (loss) 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, after tax and before adjustment, of unrealized holding gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Excludes unrealized gain (loss) on investment in debt security measured at amortized cost (held-to-maturity) from transfer to available-for-sale.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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