Investments: Available-for-sale Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Debt Securities, Available-for-sale [Line Items]
Investments available-for-sale, at fair value	$ 217,778	$ 168,948
Debt Securities, Available-for-sale, Unrealized Loss	18,190	1,459
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	41	1,656
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, after Allowance for Credit Loss	235,927	168,751
Mortgage-backed investments, Fannie Mae
Debt Securities, Available-for-sale [Line Items]
Investments available-for-sale, at fair value	9,940	12,978
Debt Securities, Available-for-sale, Unrealized Loss	1,860	88
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	0	146
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, after Allowance for Credit Loss	11,800	12,920
Mortgage-backed investments, Freddie Mac
Debt Securities, Available-for-sale [Line Items]
Investments available-for-sale, at fair value	11,889	12,824
Debt Securities, Available-for-sale, Unrealized Loss	1,831	330
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	0	115
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, after Allowance for Credit Loss	13,720	13,039
Mortgage backed investments Ginnie Mae
Debt Securities, Available-for-sale [Line Items]
Investments available-for-sale, at fair value	27,843	23,687
Debt Securities, Available-for-sale, Unrealized Loss	1,601	146
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	18	105
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, after Allowance for Credit Loss	29,426	23,728
Other
Debt Securities, Available-for-sale [Line Items]
Investments available-for-sale, at fair value	32,389	11,264
Debt Securities, Available-for-sale, Unrealized Loss	1,906	61
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	0	47
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, after Allowance for Credit Loss	34,295	11,278
Municipal Bonds
Debt Securities, Available-for-sale [Line Items]
Investments available-for-sale, at fair value	30,883	36,466
Debt Securities, Available-for-sale, Unrealized Loss	6,102	289
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	17	677
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, after Allowance for Credit Loss	36,968	36,078
US Government agencies
Debt Securities, Available-for-sale [Line Items]
Investments available-for-sale, at fair value	74,354	41,434
Debt Securities, Available-for-sale, Unrealized Loss	2,370	338
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	6	61
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, after Allowance for Credit Loss	76,718	41,711
Corporate Bonds
Debt Securities, Available-for-sale [Line Items]
Investments available-for-sale, at fair value	30,480	30,295
Debt Securities, Available-for-sale, Unrealized Loss	2,520	207
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	0	505
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, after Allowance for Credit Loss	$ 33,000	$ 29,997

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27161-111563

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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) 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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-Publisher FASB
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-Topic 320
-SubTopic 10
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-Paragraph 2
-Subparagraph (c)
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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).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454

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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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