Loans Receivable, Allowance for Credit Losses and Credit Quality - Aging of the Amortized Cost of Loans Receivables (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Loans Receivable and ACL
Total loans, gross	$ 4,722,951	$ 4,339,468
Nonaccrual	11,357	13,856
Current Loans
Loans Receivable and ACL
Total loans, gross	4,702,560	4,305,967
30-59 Days Past Due
Loans Receivable and ACL
Total loans, gross	3,356	17,091
60-89 Days Past Due
Loans Receivable and ACL
Total loans, gross	4,351	2,554
90 Days or More
Loans Receivable and ACL
Past Due 90 Days or More & Still Accruing	1,327
Residential real estate
Loans Receivable and ACL
Total loans, gross	1,272,835	1,254,832
Residential real estate \| One to four-family residential
Loans Receivable and ACL
Total loans, gross	1,133,856	1,130,791
Nonaccrual	2,600	2,930
Residential real estate \| One to four-family residential \| Current Loans
Loans Receivable and ACL
Total loans, gross	1,130,365	1,124,762
Residential real estate \| One to four-family residential \| 30-59 Days Past Due
Loans Receivable and ACL
Total loans, gross	377	2,363
Residential real estate \| One to four-family residential \| 60-89 Days Past Due
Loans Receivable and ACL
Total loans, gross	343	736
Residential real estate \| One to four-family residential \| 90 Days or More
Loans Receivable and ACL
Past Due 90 Days or More & Still Accruing	171
Residential real estate \| Home equity
Loans Receivable and ACL
Total loans, gross	138,979	124,041
Nonaccrual	1,172	958
Residential real estate \| Home equity \| Current Loans
Loans Receivable and ACL
Total loans, gross	137,620	122,812
Residential real estate \| Home equity \| 30-59 Days Past Due
Loans Receivable and ACL
Total loans, gross	187	100
Residential real estate \| Home equity \| 60-89 Days Past Due
Loans Receivable and ACL
Total loans, gross		171
Residential real estate \| Commercial real estate
Loans Receivable and ACL
Total loans, gross	1,449,675	1,363,394
Nonaccrual	809	3,005
Residential real estate \| Commercial real estate \| Current Loans
Loans Receivable and ACL
Total loans, gross	1,447,710	1,355,064
Residential real estate \| Commercial real estate \| 30-59 Days Past Due
Loans Receivable and ACL
Total loans, gross		5,325
Residential real estate \| Commercial real estate \| 90 Days or More
Loans Receivable and ACL
Past Due 90 Days or More & Still Accruing	1,156
Residential real estate \| Multi-family residential
Loans Receivable and ACL
Total loans, gross	430,428	333,047
Residential real estate \| Multi-family residential \| Current Loans
Loans Receivable and ACL
Total loans, gross	430,428	332,740
Residential real estate \| Multi-family residential \| 30-59 Days Past Due
Loans Receivable and ACL
Total loans, gross		307
Residential real estate \| Construction & land development
Loans Receivable and ACL
Total loans, gross	655,023	583,809
Nonaccrual	10	10
Residential real estate \| Construction & land development \| Current Loans
Loans Receivable and ACL
Total loans, gross	655,013	583,435
Residential real estate \| Construction & land development \| 30-59 Days Past Due
Loans Receivable and ACL
Total loans, gross		364
Commercial
Loans Receivable and ACL
Total loans, gross	3,186,857	2,840,078
Commercial \| Construction & land development
Loans Receivable and ACL
Total loans, gross	655,023	583,809
Commercial \| Commercial and industrial
Loans Receivable and ACL
Total loans, gross	651,731	559,828
Nonaccrual	4,686	4,558
Commercial \| Commercial and industrial \| Current Loans
Loans Receivable and ACL
Total loans, gross	644,657	550,353
Commercial \| Commercial and industrial \| 30-59 Days Past Due
Loans Receivable and ACL
Total loans, gross		4,907
Commercial \| Commercial and industrial \| 60-89 Days Past Due
Loans Receivable and ACL
Total loans, gross	2,388	10
Consumer
Loans Receivable and ACL
Total loans, gross	263,259	244,558
Nonaccrual	2,080	2,395
Consumer \| Current Loans
Loans Receivable and ACL
Total loans, gross	256,767	236,801
Consumer \| 30-59 Days Past Due
Loans Receivable and ACL
Total loans, gross	2,792	3,725
Consumer \| 60-89 Days Past Due
Loans Receivable and ACL
Total loans, gross	$ 1,620	$ 1,637

Amortized cost excluding accrued interest, of financing receivable 90 days or more past due and still accruing. Excludes net investment in lease.

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