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LOANS AND ALLOWANCE FOR CREDIT LOSSES - Credit Quality By Past Due Status (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Aged analysis of the company's loans
Total Loans	$ 9,704,598	$ 8,809,394
Interest income on nonaccrual loans	0	0
Interest income on loans	400
Legacy Loan
Aged analysis of the company's loans
Total Loans	9,704,598	8,809,394
Nonaccrual	48,687	29,245
Legacy Loan | Past Due 30 - 89 Days
Aged analysis of the company's loans
Total Loans	48,442	45,244
Legacy Loan | 90+ Days Past Due and Still Accruing
Aged analysis of the company's loans
Total Loans	5,886	4,119
Legacy Loan | Financial Asset, Past Due
Aged analysis of the company's loans
Total Loans	103,015	78,608
Legacy Loan | Financial Asset, Not Past Due
Aged analysis of the company's loans
Total Loans	9,601,583	8,730,786
CRE - multifamily
Aged analysis of the company's loans
Total Loans	619,794	484,773
CRE - owner occupied
Aged analysis of the company's loans
Total Loans	752,774	722,387
CRE - non-owner occupied
Aged analysis of the company's loans
Total Loans	1,711,198	1,431,720
Commercial & industrial and other business loans
Aged analysis of the company's loans
Total Loans	1,000,630	1,006,785
Business lending
Aged analysis of the company's loans
Total Loans	4,084,396	3,645,665
Consumer mortgage
Aged analysis of the company's loans
Total Loans	3,285,018	3,012,475
Consumer indirect
Aged analysis of the company's loans
Total Loans	1,703,440	1,539,653
Consumer direct
Aged analysis of the company's loans
Total Loans	185,229	177,605
Home equity
Aged analysis of the company's loans
Total Loans	446,515	433,996
Commercial Portfolio Segment | CRE - multifamily
Aged analysis of the company's loans
Total Loans	619,794	484,773
Commercial Portfolio Segment | CRE - multifamily | Legacy Loan
Aged analysis of the company's loans
Total Loans	619,794	484,773
Nonaccrual	0	0
Commercial Portfolio Segment | CRE - multifamily | Legacy Loan | Past Due 30 - 89 Days
Aged analysis of the company's loans
Total Loans	0	0
Commercial Portfolio Segment | CRE - multifamily | Legacy Loan | 90+ Days Past Due and Still Accruing
Aged analysis of the company's loans
Total Loans	0	0
Commercial Portfolio Segment | CRE - multifamily | Legacy Loan | Financial Asset, Past Due
Aged analysis of the company's loans
Total Loans	0	0
Commercial Portfolio Segment | CRE - multifamily | Legacy Loan | Financial Asset, Not Past Due
Aged analysis of the company's loans
Total Loans	619,794	484,773
Commercial Portfolio Segment | CRE - owner occupied
Aged analysis of the company's loans
Total Loans	752,774	722,387
Commercial Portfolio Segment | CRE - non-owner occupied
Aged analysis of the company's loans
Total Loans	1,711,198	1,431,720
Commercial Portfolio Segment | Commercial & industrial and other business loans
Aged analysis of the company's loans
Total Loans	1,000,630	1,006,785
Residential Portfolio Segment | CRE - owner occupied | Legacy Loan
Aged analysis of the company's loans
Total Loans	752,774	722,387
Nonaccrual	1,953	2,977
Residential Portfolio Segment | CRE - owner occupied | Legacy Loan | Past Due 30 - 89 Days
Aged analysis of the company's loans
Total Loans	1,477	2,332
Residential Portfolio Segment | CRE - owner occupied | Legacy Loan | 90+ Days Past Due and Still Accruing
Aged analysis of the company's loans
Total Loans	0	0
Residential Portfolio Segment | CRE - owner occupied | Legacy Loan | Financial Asset, Past Due
Aged analysis of the company's loans
Total Loans	3,430	5,309
Residential Portfolio Segment | CRE - owner occupied | Legacy Loan | Financial Asset, Not Past Due
Aged analysis of the company's loans
Total Loans	749,344	717,078
Residential Portfolio Segment | Consumer mortgage
Aged analysis of the company's loans
Total Loans	3,285,018	3,012,475
Residential Portfolio Segment | Consumer mortgage | Legacy Loan
Aged analysis of the company's loans
Total Loans	3,285,018	3,012,475
Nonaccrual	26,043	22,583
Residential Portfolio Segment | Consumer mortgage | Legacy Loan | Past Due 30 - 89 Days
Aged analysis of the company's loans
Total Loans	18,434	13,757
Residential Portfolio Segment | Consumer mortgage | Legacy Loan | 90+ Days Past Due and Still Accruing
Aged analysis of the company's loans
Total Loans	4,559	3,510
Residential Portfolio Segment | Consumer mortgage | Legacy Loan | Financial Asset, Past Due
Aged analysis of the company's loans
Total Loans	49,036	39,850
Residential Portfolio Segment | Consumer mortgage | Legacy Loan | Financial Asset, Not Past Due
Aged analysis of the company's loans
Total Loans	3,235,982	2,972,625
Residential Portfolio Segment | Home equity | Legacy Loan
Aged analysis of the company's loans
Total Loans	446,515	433,996
Nonaccrual	2,368	1,945
Residential Portfolio Segment | Home equity | Legacy Loan | Past Due 30 - 89 Days
Aged analysis of the company's loans
Total Loans	3,546	3,595
Residential Portfolio Segment | Home equity | Legacy Loan | 90+ Days Past Due and Still Accruing
Aged analysis of the company's loans
Total Loans	416	299
Residential Portfolio Segment | Home equity | Legacy Loan | Financial Asset, Past Due
Aged analysis of the company's loans
Total Loans	6,330	5,839
Residential Portfolio Segment | Home equity | Legacy Loan | Financial Asset, Not Past Due
Aged analysis of the company's loans
Total Loans	440,185	428,157
Consumer Portfolio Segment | CRE - non-owner occupied | Legacy Loan
Aged analysis of the company's loans
Total Loans	1,711,198	1,431,720
Nonaccrual	17,964	1,365
Consumer Portfolio Segment | CRE - non-owner occupied | Legacy Loan | Past Due 30 - 89 Days
Aged analysis of the company's loans
Total Loans	2,311	5,703
Consumer Portfolio Segment | CRE - non-owner occupied | Legacy Loan | 90+ Days Past Due and Still Accruing
Aged analysis of the company's loans
Total Loans	0	0
Consumer Portfolio Segment | CRE - non-owner occupied | Legacy Loan | Financial Asset, Past Due
Aged analysis of the company's loans
Total Loans	20,275	7,068
Consumer Portfolio Segment | CRE - non-owner occupied | Legacy Loan | Financial Asset, Not Past Due
Aged analysis of the company's loans
Total Loans	1,690,923	1,424,652
Consumer Portfolio Segment | Commercial & industrial and other business loans | Legacy Loan
Aged analysis of the company's loans
Total Loans	1,000,630	1,006,785
Nonaccrual	336	347
Consumer Portfolio Segment | Commercial & industrial and other business loans | Legacy Loan | Past Due 30 - 89 Days
Aged analysis of the company's loans
Total Loans	880	1,783
Consumer Portfolio Segment | Commercial & industrial and other business loans | Legacy Loan | 90+ Days Past Due and Still Accruing
Aged analysis of the company's loans
Total Loans	0	0
Consumer Portfolio Segment | Commercial & industrial and other business loans | Legacy Loan | Financial Asset, Past Due
Aged analysis of the company's loans
Total Loans	1,216	2,130
Consumer Portfolio Segment | Commercial & industrial and other business loans | Legacy Loan | Financial Asset, Not Past Due
Aged analysis of the company's loans
Total Loans	999,414	1,004,655
Consumer Portfolio Segment | Consumer indirect
Aged analysis of the company's loans
Total Loans	1,703,440	1,539,653
Consumer Portfolio Segment | Consumer indirect | Legacy Loan
Aged analysis of the company's loans
Total Loans	1,703,440	1,539,653
Nonaccrual	0	0
Consumer Portfolio Segment | Consumer indirect | Legacy Loan | Past Due 30 - 89 Days
Aged analysis of the company's loans
Total Loans	20,215	16,767
Consumer Portfolio Segment | Consumer indirect | Legacy Loan | 90+ Days Past Due and Still Accruing
Aged analysis of the company's loans
Total Loans	776	178
Consumer Portfolio Segment | Consumer indirect | Legacy Loan | Financial Asset, Past Due
Aged analysis of the company's loans
Total Loans	20,991	16,945
Consumer Portfolio Segment | Consumer indirect | Legacy Loan | Financial Asset, Not Past Due
Aged analysis of the company's loans
Total Loans	1,682,449	1,522,708
Consumer Portfolio Segment | Consumer direct
Aged analysis of the company's loans
Total Loans	185,229	177,605
Consumer Portfolio Segment | Consumer direct | Legacy Loan
Aged analysis of the company's loans
Total Loans	185,229	177,605
Nonaccrual	23	28
Consumer Portfolio Segment | Consumer direct | Legacy Loan | Past Due 30 - 89 Days
Aged analysis of the company's loans
Total Loans	1,579	1,307
Consumer Portfolio Segment | Consumer direct | Legacy Loan | 90+ Days Past Due and Still Accruing
Aged analysis of the company's loans
Total Loans	135	132
Consumer Portfolio Segment | Consumer direct | Legacy Loan | Financial Asset, Past Due
Aged analysis of the company's loans
Total Loans	1,737	1,467
Consumer Portfolio Segment | Consumer direct | Legacy Loan | Financial Asset, Not Past Due
Aged analysis of the company's loans
Total Loans	183,492	176,138
Consumer Portfolio Segment | Home equity
Aged analysis of the company's loans
Total Loans	$ 446,515	$ 433,996

X

- Definition

Loans acquired after January 1, 2009 that have evidence of deterioration in credit quality since origination and for which it is probable, at acquisition, that the company will be unable to collect all contractually required payments.

+ References

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- Definition

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+ References

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