Investments: Available-for-sale Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 177,388	$ 125,685
Gross Unrealized Gains	2,218	2,680
Gross Unrealized Losses	(1,545)	(814)
Fair Value	178,061	127,551
Mortgage-backed investments, Fannie Mae
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	15,175	12,797
Gross Unrealized Gains	276	491
Gross Unrealized Losses	(64)	0
Fair Value	15,387	13,288
Mortgage-backed investments, Freddie Mac
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	13,083	4,116
Gross Unrealized Gains	166	200
Gross Unrealized Losses	(322)	0
Fair Value	12,927	4,316
Mortgage backed investments Ginnie Mae
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	25,744	16,513
Gross Unrealized Gains	210	617
Gross Unrealized Losses	(120)	(3)
Fair Value	25,834	17,127
Other
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	5,673	10,691
Gross Unrealized Gains	93	100
Gross Unrealized Losses	(16)	(62)
Fair Value	5,750	10,729
Municipal bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	39,545	16,483
Gross Unrealized Gains	732	963
Gross Unrealized Losses	(454)	0
Fair Value	39,823	17,446
U.S. Government agencies
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	48,165	41,084
Gross Unrealized Gains	109	88
Gross Unrealized Losses	(366)	(537)
Fair Value	47,908	40,635
Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	30,003	24,001
Gross Unrealized Gains	632	221
Gross Unrealized Losses	(203)	(212)
Fair Value	$ 30,432	$ 24,010

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)
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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
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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 http://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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