Investments: Schedule of Available for sale Securities, Debt Maturities (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Investments [Abstract]
Due within one year, Amortized Cost	$ 0
Due after one year through five years, Amortized Cost	50,100
Due after five years through ten years, Amortized Cost	28,769
Due after ten years, Amortized Cost	67,817
Debt maturities, Amortized Cost	146,686
Mortgage-backed investments, Amortized Cost	89,241
Amortized Cost	235,927	$ 168,751
Due within one year, Fair Value	0
Due after one year through five years, Fair Value	48,732
Due after five years through ten years, Fair Value	26,079
Due after ten years, Fair Value	60,906
Debt maturities, Fair Value	135,717
Mortgage-backed investments, Fair Value	82,061
Investments available-for-sale, at fair value	$ 217,778	$ 168,948

Debt Securities, Amortized Cost Total

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Amountofavailable-for-saledebtsecuritiesatfairvaluematuringafterthelatestfiscalyear.

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Amountofavailable-for-saledebtsecuritiesatfairvaluematuringafterthelatestfiscalyear.

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in sixth through tenth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in sixth through tenth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in second through fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in second through fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing after tenth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amortized cost excluding accrued interest, after allowance for credit loss, 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 excluding accrued interest, 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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Fair value of securitized, pay-through debt securities collateralized by real estate mortgage loans classified as available-for-sale.

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