Loans Receivable and Allowance for Credit Losses - Allowance for Loan Losses by Portfolio Segment (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024	Dec. 31, 2024
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	$ 62,034	$ 55,401	$ 59,958	$ 55,096	$ 55,096
Initial allowance related to PCD loans	3,202		3,202
Provision for (reversal of) credit losses	2,468	2,194	5,401	7,472
Recoveries	107	270	241	419
Charge-offs	(3,344)	(803)	(4,335)	(5,925)
Balance at end of period	64,467	57,062	64,467	57,062	59,958
Commercial real estate \| One-to-four family
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	12,870	13,840	13,173	13,017	13,017
Initial allowance related to PCD loans	0		0
Provision for (reversal of) credit losses	75	1,046	(229)	1,871
Recoveries	1	2	2	2
Charge-offs	0	0	0	(2)
Balance at end of period	12,946	14,888	12,946	14,888	13,173
Commercial real estate \| Multifamily
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	9,963	8,670	9,542	8,742	8,742
Initial allowance related to PCD loans	0		0
Provision for (reversal of) credit losses	34	(279)	455	(351)
Recoveries	0	0	0	0
Charge-offs	0	0	0	0
Balance at end of period	9,997	8,391	9,997	8,391	9,542
Commercial real estate \| Commercial real estate
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	17,412	15,232	15,969	15,757	15,757
Initial allowance related to PCD loans	0		0
Provision for (reversal of) credit losses	1,548	(32)	3,067	(557)
Recoveries	0	0	1	0
Charge-offs	(42)	(120)	(119)	(120)
Balance at end of period	18,918	15,080	18,918	15,080	15,969
Commercial real estate \| Construction
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	6,263	8,068	6,703	7,758	7,758
Initial allowance related to PCD loans	0		0
Provision for (reversal of) credit losses	(449)	480	(837)	789
Recoveries	1	1	2	2
Charge-offs	0	0	(53)	0
Balance at end of period	5,815	8,549	5,815	8,549	6,703
Commercial business loans
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Initial allowance related to PCD loans	3,202		3,202
Commercial business loans \| Commercial Business
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	14,257	7,711	13,112	7,923	7,923
Provision for (reversal of) credit losses	1,201	144	3,074	4,809
Recoveries	96	262	193	405
Charge-offs	(3,248)	(623)	(4,073)	(5,643)
Balance at end of period	15,508	7,494	15,508	7,494	13,112
Consumer loans \| Home equity loans and advances
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	1,264	1,873	1,452	1,892	1,892
Initial allowance related to PCD loans	0		0
Provision for (reversal of) credit losses	6	777	(215)	753
Recoveries	7	4	40	9
Charge-offs	0	0	0	0
Balance at end of period	1,277	2,654	1,277	2,654	1,452
Consumer loans \| Other consumer loans
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	5	7	7	7	7
Initial allowance related to PCD loans	0		0
Provision for (reversal of) credit losses	53	58	86	158
Recoveries	2	1	3	1
Charge-offs	(54)	(60)	(90)	(160)
Balance at end of period	$ 6	$ 6	$ 6	$ 6	$ 7

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

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
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Amount, excluding accrued interest, of credit loss expense (reversal of expense) on financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 22
-Subparagraph (a)
-Publisher FASB
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Amount, excluding accrued interest, of allowance for credit loss at acquisition date of financing receivable purchased with credit deterioration. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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-URI https://asc.fasb.org/1943274/2147479319/326-20-50-19

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