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

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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

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-Topic 310
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-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	Jun. 30, 2025	Mar. 31, 2025	Dec. 31, 2024	Jun. 30, 2024	Mar. 31, 2024	Dec. 31, 2023
Allowance for credit losses:
Individually analyzed loans	$ 0		$ 0
Allowance for credit losses on loans	64,467	$ 62,034	59,958	$ 57,062	$ 55,401	$ 55,096
Total loans:
Individually analyzed loans	39,253		37,942
Total loans	8,138,711		7,881,133
Commercial real estate \| One-to-four family
Allowance for credit losses:
Individually analyzed loans	0		0
Allowance for credit losses on loans	12,946	12,870	13,173	14,888	13,840	13,017
Total loans:
Individually analyzed loans	11,307		9,167
Total loans	2,631,146		2,712,752
Commercial real estate \| Multifamily
Allowance for credit losses:
Individually analyzed loans	0		0
Allowance for credit losses on loans	9,997	9,963	9,542	8,391	8,670	8,742
Total loans:
Individually analyzed loans	2,026		5,743
Total loans	1,578,733		1,460,641
Commercial real estate \| Commercial real estate
Allowance for credit losses:
Individually analyzed loans	0		0
Allowance for credit losses on loans	18,918	17,412	15,969	15,080	15,232	15,757
Total loans:
Individually analyzed loans	8,321		7,517
Total loans	2,525,749		2,349,308
Commercial real estate \| Construction
Allowance for credit losses:
Allowance for credit losses on loans	5,815	6,263	6,703	8,549	8,068	7,758
Total loans:
Total loans	415,403		473,573
Commercial business loans
Allowance for credit losses:
Individually analyzed loans	0		0
Total loans:
Individually analyzed loans	10,956		15,184
Commercial business loans \| Commercial Business
Allowance for credit losses:
Allowance for credit losses on loans	15,508	14,257	13,112	7,494	7,711	7,923
Total loans:
Total loans	728,694		622,300
Consumer loans \| Home equity loans and advances
Allowance for credit losses:
Individually analyzed loans	0		0
Allowance for credit losses on loans	1,277	1,264	1,452	2,654	1,873	1,892
Total loans:
Individually analyzed loans	720		331
Total loans	256,384		259,155
Consumer loans \| Other consumer loans
Allowance for credit losses:
Allowance for credit losses on loans	6	$ 5	7	$ 6	$ 7	$ 7
Total loans:
Total loans	2,602		3,404
Financial Asset, Other than Financial Asset Acquired with Credit Deterioration
Allowance for credit losses:
Individually analyzed loans	0		0
Collectively analyzed loans	64,410		59,925
Total loans:
Individually analyzed loans	39,253		37,942
Collectively analyzed loans	8,087,460		7,831,505
Total loans	8,126,713		7,869,447
Financial Asset, Other than Financial Asset Acquired with Credit Deterioration \| Commercial real estate \| One-to-four family
Allowance for credit losses:
Individually analyzed loans	0		0
Collectively analyzed loans	12,942		13,169
Total loans:
Individually analyzed loans	11,307		9,167
Collectively analyzed loans	2,618,065		2,701,770
Total loans	2,629,372		2,710,937
Financial Asset, Other than Financial Asset Acquired with Credit Deterioration \| Commercial real estate \| Multifamily
Allowance for credit losses:
Individually analyzed loans	0		0
Collectively analyzed loans	9,997		9,542
Total loans:
Individually analyzed loans	2,026		5,743
Collectively analyzed loans	1,576,707		1,454,898
Total loans	1,578,733		1,460,641
Financial Asset, Other than Financial Asset Acquired with Credit Deterioration \| Commercial real estate \| Commercial real estate
Allowance for credit losses:
Individually analyzed loans	0		0
Collectively analyzed loans	18,888		15,940
Total loans:
Individually analyzed loans	8,321		7,517
Collectively analyzed loans	2,509,372		2,332,366
Total loans	2,517,693		2,339,883
Financial Asset, Other than Financial Asset Acquired with Credit Deterioration \| Commercial real estate \| Construction
Allowance for credit losses:
Individually analyzed loans	0		0
Collectively analyzed loans	5,815		6,703
Total loans:
Individually analyzed loans	5,923		0
Collectively analyzed loans	409,480		473,573
Total loans	415,403		473,573
Financial Asset, Other than Financial Asset Acquired with Credit Deterioration \| Commercial business loans
Total loans:
Total loans	726,526		622,000
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	15,485		13,112
Total loans:
Individually analyzed loans	10,956		15,184
Collectively analyzed loans	715,570		606,816
Financial Asset, Other than Financial Asset Acquired with Credit Deterioration \| Consumer loans \| Home equity loans and advances
Allowance for credit losses:
Individually analyzed loans	0		0
Collectively analyzed loans	1,277		1,452
Total loans:
Individually analyzed loans	720		331
Collectively analyzed loans	255,664		258,678
Total loans	256,384		259,009
Financial Asset, Other than Financial Asset Acquired with Credit Deterioration \| Consumer loans \| Other consumer loans
Allowance for credit losses:
Individually analyzed loans	0		0
Collectively analyzed loans	6		7
Total loans:
Individually analyzed loans	0		0
Collectively analyzed loans	2,602		3,404
Total loans	2,602		3,404
Financial Asset Acquired with Credit Deterioration
Allowance for credit losses:
Allowance for credit losses on loans	57		33
Total loans:
Total loans	11,998		11,686
Financial Asset Acquired with Credit Deterioration \| Commercial real estate \| One-to-four family
Allowance for credit losses:
Allowance for credit losses on loans	4		4
Total loans:
Total loans	1,774		1,815
Financial Asset Acquired with Credit Deterioration \| Commercial real estate \| 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 \| Commercial real estate \| Commercial real estate
Allowance for credit losses:
Allowance for credit losses on loans	30		29
Total loans:
Total loans	8,056		9,425
Financial Asset Acquired with Credit Deterioration \| Commercial real estate \| 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	23		0
Total loans:
Total loans	2,168		300
Financial Asset Acquired with Credit Deterioration \| Consumer loans \| Home equity loans and advances
Allowance for credit losses:
Allowance for credit losses on loans	0		0
Total loans:
Total loans	0		146
Financial Asset Acquired with Credit Deterioration \| Consumer loans \| Other consumer loans
Allowance for credit losses:
Allowance for credit losses on loans	0		0
Total loans:
Total loans	$ 0		$ 0