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LOANS AND ALLOWANCE FOR CREDIT LOSSES - Credit Quality By Past Due Status (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2023 | Sep. 30, 2023 | Dec. 31, 2022
Aged analysis of the company's loans |  |  |
Total Loans | $ 9,450,066 | $ 9,450,066 | $ 8,809,394
Interest income on nonaccrual loans | 0 | 0 |
Legacy Loan |  |  |
Aged analysis of the company's loans |  |  |
Total Loans | 9,450,066 | 9,450,066 | 8,809,394
Nonaccrual | 33,122 | 33,122 | 29,245
Legacy Loan | Past Due 30 - 89 Days |  |  |
Aged analysis of the company's loans |  |  |
Total Loans | 48,646 | 48,646 | 45,244
Legacy Loan | 90+ Days Past Due and Still Accruing |  |  |
Aged analysis of the company's loans |  |  |
Total Loans | 3,731 | 3,731 | 4,119
Legacy Loan | Financial Asset, Past Due |  |  |
Aged analysis of the company's loans |  |  |
Total Loans | 85,499 | 85,499 | 78,608
Legacy Loan | Financial Asset, Not Past Due |  |  |
Aged analysis of the company's loans |  |  |
Total Loans | 9,364,567 | 9,364,567 | 8,730,786
Business lending |  |  |
Aged analysis of the company's loans |  |  |
Total Loans | 3,914,935 | 3,914,935 | 3,645,665
Consumer mortgage |  |  |
Aged analysis of the company's loans |  |  |
Total Loans | 3,196,764 | 3,196,764 | 3,012,475
Consumer indirect |  |  |
Aged analysis of the company's loans |  |  |
Total Loans | 1,708,302 | 1,708,302 | 1,539,653
Consumer direct |  |  |
Aged analysis of the company's loans |  |  |
Total Loans | 185,301 | 185,301 | 177,605
Home equity |  |  |
Aged analysis of the company's loans |  |  |
Total Loans | 444,764 | 444,764 | 433,996
Commercial Portfolio Segment | Business lending |  |  |
Aged analysis of the company's loans |  |  |
Total Loans | 3,914,935 | 3,914,935 | 3,645,665
Commercial Portfolio Segment | Business lending | Legacy Loan |  |  |
Aged analysis of the company's loans |  |  |
Total Loans | 3,914,935 | 3,914,935 | 3,645,665
Nonaccrual | 5,638 | 5,638 | 4,689
Commercial Portfolio Segment | Business lending | Legacy Loan | Past Due 30 - 89 Days |  |  |
Aged analysis of the company's loans |  |  |
Total Loans | 13,545 | 13,545 | 9,818
Commercial Portfolio Segment | Business lending | Legacy Loan | 90+ Days Past Due and Still Accruing |  |  |
Aged analysis of the company's loans |  |  |
Total Loans | 0 | 0 | 0
Commercial Portfolio Segment | Business lending | Legacy Loan | Financial Asset, Past Due |  |  |
Aged analysis of the company's loans |  |  |
Total Loans | 19,183 | 19,183 | 14,507
Commercial Portfolio Segment | Business lending | Legacy Loan | Financial Asset, Not Past Due |  |  |
Aged analysis of the company's loans |  |  |
Total Loans | 3,895,752 | 3,895,752 | 3,631,158
Residential Portfolio Segment | Consumer mortgage |  |  |
Aged analysis of the company's loans |  |  |
Total Loans | 3,196,764 | 3,196,764 | 3,012,475
Residential Portfolio Segment | Consumer mortgage | Legacy Loan |  |  |
Aged analysis of the company's loans |  |  |
Total Loans | 3,196,764 | 3,196,764 | 3,012,475
Nonaccrual | 25,205 | 25,205 | 22,583
Residential Portfolio Segment | Consumer mortgage | Legacy Loan | Past Due 30 - 89 Days |  |  |
Aged analysis of the company's loans |  |  |
Total Loans | 15,282 | 15,282 | 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 | 2,908 | 2,908 | 3,510
Residential Portfolio Segment | Consumer mortgage | Legacy Loan | Financial Asset, Past Due |  |  |
Aged analysis of the company's loans |  |  |
Total Loans | 43,395 | 43,395 | 39,850
Residential Portfolio Segment | Consumer mortgage | Legacy Loan | Financial Asset, Not Past Due |  |  |
Aged analysis of the company's loans |  |  |
Total Loans | 3,153,369 | 3,153,369 | 2,972,625
Residential Portfolio Segment | Home equity |  |  |
Aged analysis of the company's loans |  |  |
Total Loans | 444,764 | 444,764 | 433,996
Residential Portfolio Segment | Home equity | Legacy Loan |  |  |
Aged analysis of the company's loans |  |  |
Total Loans | 444,764 | 444,764 | 433,996
Nonaccrual | 2,255 | 2,255 | 1,945
Residential Portfolio Segment | Home equity | Legacy Loan | Past Due 30 - 89 Days |  |  |
Aged analysis of the company's loans |  |  |
Total Loans | 3,331 | 3,331 | 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 | 504 | 504 | 299
Residential Portfolio Segment | Home equity | Legacy Loan | Financial Asset, Past Due |  |  |
Aged analysis of the company's loans |  |  |
Total Loans | 6,090 | 6,090 | 5,839
Residential Portfolio Segment | Home equity | Legacy Loan | Financial Asset, Not Past Due |  |  |
Aged analysis of the company's loans |  |  |
Total Loans | 438,674 | 438,674 | 428,157
Consumer Portfolio Segment | Consumer indirect |  |  |
Aged analysis of the company's loans |  |  |
Total Loans | 1,708,302 | 1,708,302 | 1,539,653
Consumer Portfolio Segment | Consumer indirect | Legacy Loan |  |  |
Aged analysis of the company's loans |  |  |
Total Loans | 1,708,302 | 1,708,302 | 1,539,653
Nonaccrual | 0 | 0 | 0
Consumer Portfolio Segment | Consumer indirect | Legacy Loan | Past Due 30 - 89 Days |  |  |
Aged analysis of the company's loans |  |  |
Total Loans | 15,175 | 15,175 | 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 | 290 | 290 | 178
Consumer Portfolio Segment | Consumer indirect | Legacy Loan | Financial Asset, Past Due |  |  |
Aged analysis of the company's loans |  |  |
Total Loans | 15,465 | 15,465 | 16,945
Consumer Portfolio Segment | Consumer indirect | Legacy Loan | Financial Asset, Not Past Due |  |  |
Aged analysis of the company's loans |  |  |
Total Loans | 1,692,837 | 1,692,837 | 1,522,708
Consumer Portfolio Segment | Consumer direct |  |  |
Aged analysis of the company's loans |  |  |
Total Loans | 185,301 | 185,301 | 177,605
Consumer Portfolio Segment | Consumer direct | Legacy Loan |  |  |
Aged analysis of the company's loans |  |  |
Total Loans | 185,301 | 185,301 | 177,605
Nonaccrual | 24 | 24 | 28
Consumer Portfolio Segment | Consumer direct | Legacy Loan | Past Due 30 - 89 Days |  |  |
Aged analysis of the company's loans |  |  |
Total Loans | 1,313 | 1,313 | 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 | 29 | 29 | 132
Consumer Portfolio Segment | Consumer direct | Legacy Loan | Financial Asset, Past Due |  |  |
Aged analysis of the company's loans |  |  |
Total Loans | 1,366 | 1,366 | 1,467
Consumer Portfolio Segment | Consumer direct | Legacy Loan | Financial Asset, Not Past Due |  |  |
Aged analysis of the company's loans |  |  |
Total Loans | $ 183,935 | $ 183,935 | $ 176,138

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