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LOANS AND ALLOWANCE FOR CREDIT LOSSES - Loan Summary (Details) - USD ($) $ in Thousands | Jun. 30, 2025 | Mar. 31, 2025 | Dec. 31, 2024 | Jun. 30, 2024 | Mar. 31, 2024 | Dec. 31, 2023
--- | --- | --- | --- | --- | --- | ---
Loans receivable, net |  |  |  |  |  |
Loans | $ 10,519,117 |  | $ 10,432,365 |  |  |
Allowance for credit losses | (81,851) |  | (79,114) | $ (71,400) |  |
Loans, net of allowance for credit losses | 10,437,266 |  | 10,353,251 |  |  |
CRE - multifamily |  |  |  |  |  |
Loans receivable, net |  |  |  |  |  |
Loans | 790,694 |  | 724,114 |  |  |
CRE - owner occupied |  |  |  |  |  |
Loans receivable, net |  |  |  |  |  |
Loans | 845,072 |  | 864,783 |  |  |
CRE - non-owner occupied |  |  |  |  |  |
Loans receivable, net |  |  |  |  |  |
Loans | 1,666,587 |  | 1,775,099 |  |  |
Commercial & industrial and other business loans |  |  |  |  |  |
Loans receivable, net |  |  |  |  |  |
Loans | 1,238,839 |  | 1,141,182 |  |  |
Consumer mortgage |  |  |  |  |  |
Loans receivable, net |  |  |  |  |  |
Loans | 3,523,025 |  | 3,489,780 |  |  |
Consumer indirect |  |  |  |  |  |
Loans receivable, net |  |  |  |  |  |
Loans | 1,767,213 |  | 1,767,655 |  |  |
Consumer direct |  |  |  |  |  |
Loans receivable, net |  |  |  |  |  |
Loans | 193,504 |  | 192,327 |  |  |
Home equity |  |  |  |  |  |
Loans receivable, net |  |  |  |  |  |
Loans | 494,183 |  | 477,425 |  |  |
Commercial Portfolio Segment | CRE - multifamily |  |  |  |  |  |
Loans receivable, net |  |  |  |  |  |
Loans | 790,694 |  | 724,114 |  |  |
Commercial Portfolio Segment | CRE - owner occupied |  |  |  |  |  |
Loans receivable, net |  |  |  |  |  |
Loans | 845,072 |  | 864,783 |  |  |
Commercial Portfolio Segment | CRE - non-owner occupied |  |  |  |  |  |
Loans receivable, net |  |  |  |  |  |
Loans | 1,666,587 |  | 1,775,099 |  |  |
Commercial Portfolio Segment | Commercial & industrial and other business loans |  |  |  |  |  |
Loans receivable, net |  |  |  |  |  |
Loans | 1,238,839 |  | 1,141,182 |  |  |
Residential Portfolio Segment | Consumer mortgage |  |  |  |  |  |
Loans receivable, net |  |  |  |  |  |
Loans | 3,523,025 |  | 3,489,780 |  |  |
Residential Portfolio Segment | Home equity |  |  |  |  |  |
Loans receivable, net |  |  |  |  |  |
Allowance for credit losses | (1,483) | $ (1,394) | (1,548) | (1,519) | $ (1,581) | $ (1,628)
Consumer Portfolio Segment | Consumer mortgage |  |  |  |  |  |
Loans receivable, net |  |  |  |  |  |
Allowance for credit losses | (14,196) | (13,679) | (15,017) | (14,303) | (14,490) | (15,333)
Consumer Portfolio Segment | Consumer indirect |  |  |  |  |  |
Loans receivable, net |  |  |  |  |  |
Loans | 1,767,213 |  | 1,767,655 |  |  |
Allowance for credit losses | (19,885) | (19,746) | (20,895) | (20,124) | (20,294) | (18,585)
Consumer Portfolio Segment | Consumer direct |  |  |  |  |  |
Loans receivable, net |  |  |  |  |  |
Loans | 193,504 |  | 192,327 |  |  |
Allowance for credit losses | (4,133) | $ (4,033) | (3,453) | $ (3,368) | $ (3,355) | $ (3,269)
Consumer Portfolio Segment | Home equity |  |  |  |  |  |
Loans receivable, net |  |  |  |  |  |
Loans | $ 494,183 |  | $ 477,425 |  |  |

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