Loans Held for Investment - Schedule of restructured loan balances, net of allowance for loan losses, by loan type and by Nonaccrual Versus Accrual Status (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Jun. 30, 2021
Financing Receivable, Modifications [Line Items]
Restructured loans on non-accrual status	$ 5,102	$ 6,983
Restructured loans on accrual status	2,773	876
Restructured loans	7,875	7,859
Mortgage loans, Single-family
Financing Receivable, Modifications [Line Items]
Restructured loans on non-accrual status	5,102	6,983
Restructured loans on accrual status	$ 2,773	$ 876

Amount of financing receivable on nonaccrual status.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123577603&loc=d3e5111-111524

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 16
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919258-210447

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph (a)
-Subparagraph (3)

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph (a)
-Subparagraph (2)

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant