Loan Servicing Rights - Analysis of the changes in MSRs (Details) - Freddie Mac - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2022
Servicing Asset at Fair Value, Amount [Roll Forward]
Balance, beginning of year	$ 2,124	$ 3,020	$ 3,438
Additions	142	113	578
Amortization	(894)	(1,009)	(1,115)
Valuation recovery	0	0	119
Balance, end of year	$ 1,372	$ 2,124	$ 3,020

The periodic amortization (in proportion to and over the period of estimated net servicing income or loss) of capitalized servicing rights, which contractually entitle the servicer to receive fees and ancillary revenues for performing billing, collection, disbursement and recordkeeping services in connection with a mortgage portfolio. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (b)
-SubTopic 10
-Topic 230
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-28

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 860
-SubTopic 50
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (a)(4)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481229/860-50-50-4

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