Financial Instruments - Summary of Investments (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2023	Dec. 31, 2022
Debt Securities, Available for Sale [Roll Forward]
Fair value at beginning of period	$ 43,485	$ 38,670
Purchases	2,472	19,771
Redemptions	(3,310)	(5,630)
Maturities	(3,505)	(6,770)
Change in bond premium	(527)	(645)
Fair market value adjustment	713	(1,911)
Fair value at end of period	$ 39,328	$ 43,485

Available-for-sale securities, debt securities, fair market value adjustment.

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Debt Securities, Available for Sale

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Increase (Decrease) in bond premium.

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Amount 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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Amount of cash outflow to acquire 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 of cash inflow from maturity, prepayment and call 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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