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SHAREHOLDERS' EQUITY - Regulatory Capital Requirements (Details) $ in Thousands | Dec. 31, 2023 USD ($) | Dec. 31, 2022 USD ($)
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Consolidated |  |  |
Common Equity Tier 1 (to Risk Weighted Assets) |  |  |
Common Equity Tier 1 Capital |  | $ 690,296 | $ 687,686
Common Equity Tier 1 Capital for Capital Adequacy Purposes |  | $ 252,954 | $ 245,107
Common Equity Tier 1 (to Risk Weighted Assets) Ratios [Abstract] |  |  |
Common Equity Tier 1 Capital to Risk Weighted Assets |  | 0.1228 | 0.1263
Common Equity Tier 1 Capital Required for Capital Adequacy Purposes to Risk Weighted Assets |  | 0.0450 | 0.0450
Tier 1 Capital (to Risk Weighted Assets) |  |  |
Tier 1 Capital |  | $ 748,755 | $ 746,140
Tier 1 Capital Required for Capital Adequacy Purposes |  | $ 337,273 | $ 326,809
Tier 1 Capital (to Risk Weighted Assets) Ratios |  |  |
Tier 1 Capital to Risk Weighted Assets |  | 0.1332 | 0.1370
Tier 1 Capital Required for Capital Adequacy Purposes to Risk Weighted Assets |  | 0.0600 | 0.0600
Total Capital (to Risk Weighted Assets) |  |  |
Total Capital |  | $ 884,095 | $ 877,281
Total Capital Required for Capital Adequacy Purposes |  | $ 449,697 | $ 435,746
Total Capital (to Risk Weighted Assets) Ratios |  |  |
Total Capital to Risk Weighted Assets |  | 0.1573 | 0.1611
Total Capital Required for Capital Adequacy Purposes to Risk Weighted Assets |  | 0.0800 | 0.0800
Tier 1 Capital (to Average Assets) |  |  |
Tier 1 Capital | [1] | $ 748,755 | $ 746,140
Tier 1 Capital Required for Capital Adequacy Purposes | [1] | $ 318,906 | $ 299,511
Tier 1 Capital (to Average Assets) Ratios |  |  |
Tier 1 Capital to Average Assets | [1] | 0.0939 | 0.0996
Tier 1 Capital Required for Capital Adequacy Purposes to Average Assets | [1] | 0.0400 | 0.0400
Bank Only |  |  |
Common Equity Tier 1 (to Risk Weighted Assets) |  |  |
Common Equity Tier 1 Capital |  | $ 836,228 | $ 823,323
Common Equity Tier 1 Capital for Capital Adequacy Purposes |  | 252,865 | 245,085
Common Equity Tier 1 Capital to be Well Capitalized |  | $ 365,249 | $ 354,012
Common Equity Tier 1 (to Risk Weighted Assets) Ratios [Abstract] |  |  |
Common Equity Tier 1 Capital to Risk Weighted Assets |  | 0.1488 | 0.1512
Common Equity Tier 1 Capital Required for Capital Adequacy Purposes to Risk Weighted Assets |  | 0.0450 | 0.0450
Common Equity Tier 1 Capital Required to be Well Capitalized to Risk Weighted Assets |  | 0.0650 | 0.0650
Tier 1 Capital (to Risk Weighted Assets) |  |  |
Tier 1 Capital |  | $ 836,228 | $ 823,323
Tier 1 Capital Required for Capital Adequacy Purposes |  | 337,153 | 326,780
Tier 1 Capital Required to be Well Capitalized |  | $ 449,537 | $ 435,707
Tier 1 Capital (to Risk Weighted Assets) Ratios |  |  |
Tier 1 Capital to Risk Weighted Assets |  | 0.1488 | 0.1512
Tier 1 Capital Required for Capital Adequacy Purposes to Risk Weighted Assets |  | 0.0600 | 0.0600
Tier 1 Capital Required to be Well Capitalized to Risk Weighted Assets |  | 0.0800 | 0.0800
Total Capital (to Risk Weighted Assets) |  |  |
Total Capital |  | $ 877,691 | $ 855,790
Total Capital Required for Capital Adequacy Purposes |  | 449,537 | 435,707
Total Capital Required to be Well Capitalized |  | $ 561,922 | $ 544,633
Total Capital (to Risk Weighted Assets) Ratios |  |  |
Total Capital to Risk Weighted Assets |  | 0.1562 | 0.1571
Total Capital Required for Capital Adequacy Purposes to Risk Weighted Assets |  | 0.0800 | 0.0800
Total Capital Required to be Well Capitalized to Risk Weighted Assets |  | 0.1000 | 0.1000
Tier 1 Capital (to Average Assets) |  |  |
Tier 1 Capital | [1] | $ 836,228 | $ 823,323
Tier 1 Capital Required for Capital Adequacy Purposes | [1] | 318,814 | 299,410
Tier 1 Capital Required to be Well Capitalized | [1] | $ 398,517 | $ 374,263
Tier 1 Capital (to Average Assets) Ratios |  |  |
Tier 1 Capital to Average Assets | [1] | 0.1049 | 0.1100
Tier 1 Capital Required for Capital Adequacy Purposes to Average Assets | [1] | 0.0400 | 0.0400
Tier 1 Capital Required to be Well Capitalized to Average Assets | [1] | 0.0500 | 0.0500
[1] | Refers to quarterly average assets as calculated in accordance with policies established by bank regulatory agencies.

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