Loans Receivable Held for Investment, Purchased Credit Impaired (PCI) Loans (Details) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021 USD ($) Loan	Sep. 30, 2021 USD ($) Loan	Dec. 31, 2020 USD ($)
Purchased Credit Impaired Loans [Abstract]
Number of acquired loans with evidence of credit deterioration of credit quality since origination at acquisition \| Loan	0	0
Loans receivable	$ 642,198	$ 642,198	$ 360,129
Accretable Yield on Purchased Credit Impaired Loans [Roll Forward]
Number of purchased credit impaired loans classified as nonaccrual \| Loan	0	0
Purchased Credit Impaired Loans [Member]
Purchased Credit Impaired Loans [Abstract]
Loans receivable	$ 883	$ 883
Accretable Yield on Purchased Credit Impaired Loans [Roll Forward]
Balance at the beginning of the period	327	0
Additions	0	346
Accretion	(19)	(38)
Balance at the end of the period	308	308
Real Estate [Member] \| Single Family [Member] \| Purchased Credit Impaired Loans [Member]
Purchased Credit Impaired Loans [Abstract]
Loans receivable	558	558
Real Estate [Member] \| Commercial Real Estate [Member] \| Purchased Credit Impaired Loans [Member]
Purchased Credit Impaired Loans [Abstract]
Loans receivable	221	221
Commercial - Other [Member] \| Purchased Credit Impaired Loans [Member]
Purchased Credit Impaired Loans [Abstract]
Loans receivable	$ 104	$ 104

Number of acquired loans with evidence of credit deterioration of credit quality since origination at acquisition.

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- Definition

The number of purchased credit impaired loans that were classified as nonaccrual.

+ References

No definition available.

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- References

No definition available.

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- Definition

Amount of the excess of a loan's cash flows expected to be collected over the investor's initial investment in acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 15
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=123409700&loc=d3e13503-111538

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=121614798&loc=d3e15032-111544

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- Definition

Amount of accretion recognized for the excess of a loan's cash flows expected to be collected over the investor's initial investment in acquired loans not accounted for as debt securities, with evidence of deterioration of credit quality.

+ References

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- Definition

Amount of additions to the excess of a loan's cash flows expected to be collected over the investor's initial investment in acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

+ References

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Amount, after allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919230-210447

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(3))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=124259787&loc=d3e4428-111522

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