Financial Instruments - Summary of Investments (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2022	Dec. 31, 2021
Debt Securities, Available for Sale [Roll Forward]
Fair value at beginning of period	$ 38,670	$ 25,708
Purchases	8,450	26,980
Redemptions	(400)	(6,530)
Maturities	(1,970)	(8,347)
Change in bond premium	206	1,517
Fair market value adjustment	(1,291)	(658)
Fair value at end of period	$ 43,665	$ 38,670

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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