Allowance for Loan and Lease Losses [Abstract]

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- Definition

Total Loans [Abstract]

+ References

No definition available.

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- Definition

Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479344/326-20-45-1

+ Details

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 4
-Subparagraph (SAB Topic 6.L.5.a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480418/310-10-S99-4

Reference 2: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 11B
-Subparagraph (g)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-11B

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 30
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479391/326-20-30-2

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- Definition

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

+ References

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- Definition

Amount of financing receivable collectively evaluated for credit loss. Excludes financing receivable individually evaluated for credit loss.

+ References

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- Definition

Amortized cost excluding accrued interest, before allowance for credit loss, fee, and loan in process, of financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(7))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1

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- Definition

Amount of financing receivable individually evaluated for credit loss. Excludes financing receivable collectively evaluated for credit loss.

+ References

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Loans Receivable and Allowance for Credit Losses - Allowance for Credit Losses (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025	Mar. 31, 2025	Dec. 31, 2024
Allowance for credit losses:
Individually analyzed loans	$ 0	$ 0
Allowance for credit losses on loans	68,761	67,201	$ 62,034	$ 59,958
Total loans:
Individually analyzed loans	37,765	37,623
Total loans	8,221,307	8,253,818
Real estate loans \| One-to-four family
Allowance for credit losses:
Individually analyzed loans	0	0
Allowance for credit losses on loans	13,229	13,283	12,870	13,173
Total loans:
Individually analyzed loans	10,999	10,988
Total loans	2,544,838	2,559,519
Real estate loans \| Multifamily
Allowance for credit losses:
Individually analyzed loans	0	0
Allowance for credit losses on loans	10,128	10,647	9,963	9,542
Total loans:
Individually analyzed loans	10,791	300
Total loans	1,669,232	1,677,613
Real estate loans \| Commercial real estate
Allowance for credit losses:
Individually analyzed loans	0	0
Allowance for credit losses on loans	18,930	18,592	17,412	15,969
Total loans:
Individually analyzed loans	6,504	5,492
Total loans	2,480,804	2,521,151
Real estate loans \| Construction
Allowance for credit losses:
Individually analyzed loans		0
Allowance for credit losses on loans	7,968	6,617	6,263	6,703
Total loans:
Individually analyzed loans		5,923
Total loans	520,753	469,438
Commercial business loans
Allowance for credit losses:
Individually analyzed loans	0	0
Total loans:
Individually analyzed loans	8,465	13,658
Commercial business loans \| Commercial business
Allowance for credit losses:
Allowance for credit losses on loans	17,224	16,767	14,257	13,112
Total loans:
Total loans	753,343	768,076
Home equity loans and advances \| Home equity loans and advances
Allowance for credit losses:
Individually analyzed loans	0	0
Allowance for credit losses on loans	1,276	1,289	1,264	1,452
Total loans:
Individually analyzed loans	1,006	1,262
Total loans	249,487	255,126
Home equity loans and advances \| Other consumer loans
Allowance for credit losses:
Allowance for credit losses on loans	6	6	$ 5	$ 7
Total loans:
Total loans	2,850	2,895
Financial Asset, Other than Financial Asset Acquired with Credit Deterioration
Allowance for credit losses:
Individually analyzed loans	0	0
Collectively analyzed loans	68,716	67,155
Total loans:
Individually analyzed loans	37,765	37,623
Collectively analyzed loans	8,173,384	8,205,753
Total loans	8,211,149	8,243,376
Financial Asset, Other than Financial Asset Acquired with Credit Deterioration \| Real estate loans \| One-to-four family
Allowance for credit losses:
Individually analyzed loans	0	0
Collectively analyzed loans	13,226	13,280
Total loans:
Individually analyzed loans	10,999	10,988
Collectively analyzed loans	2,532,589	2,547,264
Total loans	2,543,588	2,558,252
Financial Asset, Other than Financial Asset Acquired with Credit Deterioration \| Real estate loans \| Multifamily
Allowance for credit losses:
Individually analyzed loans	0	0
Collectively analyzed loans	10,128	10,647
Total loans:
Individually analyzed loans	10,791	300
Collectively analyzed loans	1,658,441	1,677,313
Total loans	1,669,232	1,677,613
Financial Asset, Other than Financial Asset Acquired with Credit Deterioration \| Real estate loans \| Commercial real estate
Allowance for credit losses:
Individually analyzed loans	0	0
Collectively analyzed loans	18,900	18,563
Total loans:
Individually analyzed loans	6,504	5,492
Collectively analyzed loans	2,466,489	2,507,768
Total loans	2,472,993	2,513,260
Financial Asset, Other than Financial Asset Acquired with Credit Deterioration \| Real estate loans \| Construction
Allowance for credit losses:
Individually analyzed loans	0	0
Collectively analyzed loans	7,968	6,617
Total loans:
Individually analyzed loans	0	5,923
Collectively analyzed loans	520,753	463,515
Total loans	520,753	469,438
Financial Asset, Other than Financial Asset Acquired with Credit Deterioration \| Commercial business loans
Total loans:
Total loans	752,246	766,792
Financial Asset, Other than Financial Asset Acquired with Credit Deterioration \| Commercial business loans \| Commercial business
Allowance for credit losses:
Individually analyzed loans	0	0
Collectively analyzed loans	17,212	16,753
Total loans:
Individually analyzed loans	8,465	13,658
Collectively analyzed loans	743,781	753,134
Financial Asset, Other than Financial Asset Acquired with Credit Deterioration \| Home equity loans and advances \| Home equity loans and advances
Allowance for credit losses:
Individually analyzed loans	0	0
Collectively analyzed loans	1,276	1,289
Total loans:
Individually analyzed loans	1,006	1,262
Collectively analyzed loans	248,481	253,864
Total loans	249,487	255,126
Financial Asset, Other than Financial Asset Acquired with Credit Deterioration \| Home equity loans and advances \| Other consumer loans
Allowance for credit losses:
Individually analyzed loans	0	0
Collectively analyzed loans	6	6
Total loans:
Individually analyzed loans	0	0
Collectively analyzed loans	2,850	2,895
Total loans	2,850	2,895
Financial Asset Acquired with Credit Deterioration
Allowance for credit losses:
Allowance for credit losses on loans	45	46
Total loans:
Total loans	10,158	10,442
Financial Asset Acquired with Credit Deterioration \| Real estate loans \| One-to-four family
Allowance for credit losses:
Allowance for credit losses on loans	3	3
Total loans:
Total loans	1,250	1,267
Financial Asset Acquired with Credit Deterioration \| Real estate loans \| Multifamily
Allowance for credit losses:
Allowance for credit losses on loans	0	0
Total loans:
Total loans	0	0
Financial Asset Acquired with Credit Deterioration \| Real estate loans \| Commercial real estate
Allowance for credit losses:
Allowance for credit losses on loans	30	29
Total loans:
Total loans	7,811	7,891
Financial Asset Acquired with Credit Deterioration \| Real estate loans \| Construction
Allowance for credit losses:
Allowance for credit losses on loans	0	0
Total loans:
Total loans	0	0
Financial Asset Acquired with Credit Deterioration \| Commercial business loans \| Commercial business
Allowance for credit losses:
Allowance for credit losses on loans	12	14
Total loans:
Total loans	1,097	1,284
Financial Asset Acquired with Credit Deterioration \| Home equity loans and advances \| Home equity loans and advances
Allowance for credit losses:
Allowance for credit losses on loans	0	0
Total loans:
Total loans	0	0
Financial Asset Acquired with Credit Deterioration \| Home equity loans and advances \| Other consumer loans
Allowance for credit losses:
Allowance for credit losses on loans	0	0
Total loans:
Total loans	$ 0	$ 0