Investments (Summary of Cost and Fair Value) (Details) $ in Thousands	Sep. 30, 2023 USD ($)
Amortized Cost
Due in 1 year or less	$ 51,670
Instruments not due at a single maturity date	2,275
Total	53,945
Fair Value
Due in 1 year or less	50,205
Instruments not due at a single maturity date	2,211
Total	$ 52,416

Amortized cost of 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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