Loans Receivable and Allowance for Credit Losses - Loans Individually Evaluated for Impairment (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Recorded Investment
With no allowance recorded	$ 37,765	$ 37,623
With a specific allowance recorded	0	0
Total loans	37,765	37,623
Unpaid Principal Balance
With no allowance recorded	39,778	45,259
With a specific allowance recorded	0	0
Unpaid principal balance	39,778	45,259
Specific Allowance
With no allowance recorded	0	0
With a specific allowance recorded	0	0
Specific allowance	0	0
Real estate loans \| One-to-four family
Recorded Investment
With no allowance recorded	10,999	10,988
Total loans	10,999	10,988
Unpaid Principal Balance
With no allowance recorded	11,004	10,992
Unpaid principal balance	11,004	10,992
Specific Allowance
With no allowance recorded	0	0
Specific allowance	0	0
Real estate loans \| Multifamily
Recorded Investment
With no allowance recorded	10,791	300
Total loans	10,791	300
Unpaid Principal Balance
With no allowance recorded	10,791	300
Unpaid principal balance	10,791	300
Specific Allowance
With no allowance recorded	0	0
Specific allowance	0	0
Real estate loans \| Commercial real estate
Recorded Investment
With no allowance recorded	6,504	5,492
Total loans	6,504	5,492
Unpaid Principal Balance
With no allowance recorded	6,629	5,618
Unpaid principal balance	6,629	5,618
Specific Allowance
With no allowance recorded	0	0
Specific allowance	0	0
Real estate loans \| Construction
Recorded Investment
With no allowance recorded		5,923
Total loans		5,923
Unpaid Principal Balance
With no allowance recorded		5,975
Unpaid principal balance		5,975
Specific Allowance
With no allowance recorded		0
Specific allowance		0
Commercial business loans
Recorded Investment
With no allowance recorded	8,465	13,658
Total loans	8,465	13,658
Unpaid Principal Balance
With no allowance recorded	10,348	21,112
Unpaid principal balance	10,348	21,112
Specific Allowance
With no allowance recorded	0	0
Specific allowance	0	0
Home equity loans and advances \| Home equity loans and advances
Recorded Investment
With no allowance recorded	1,006	1,262
Total loans	1,006	1,262
Unpaid Principal Balance
With no allowance recorded	1,006	1,262
Unpaid principal balance	1,006	1,262
Specific Allowance
With no allowance recorded	0	0
Specific allowance	$ 0	$ 0

Financing Receivable, Individually Evaluated for Credit Loss, Unpaid Principal Balance

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- Definition

Financing Receivable, Individually Evaluated, Specific Allowance, With Allowance For Credit Loss

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- Definition

Financing Receivable, Individually Evaluated, Specific Allowance, Without Allowance For Credit Loss

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Financing Receivable, Individually Evaluated, Unpaid Principal Balance, With Allowance For Credit Loss

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Financing Receivable, Individually Evaluated, Unpaid Principal Balance, Without Allowance For Credit Loss

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- Definition

Impaired Financing Receivable, Related Allowance

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Amount of allowance for credit loss on financing receivable evaluated on individual basis. Excludes financing receivable evaluated on collective basis.

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-Topic 310
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-Name Accounting Standards Codification
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-Paragraph 4
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-Section 30
-Paragraph 2
-Publisher FASB
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Amount of financing receivable with allowance for credit loss evaluated on individual basis. Excludes financing receivable evaluated on collective basis.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 35
-Paragraph 6
-Publisher FASB
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