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SHAREHOLDERS' EQUITY - Regulatory Capital Requirements (Details) $ in Thousands		Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Consolidated
Common Equity Tier 1 (to Risk Weighted Assets)
Common Equity Tier 1 Capital		$ 687,686	$ 657,043
Common Equity Tier 1 Capital for Capital Adequacy Purposes		$ 245,107	$ 208,616
Common Equity Tier 1 (to Risk Weighted Assets) Ratios [Abstract]
Common Equity Tier 1 Capital to Risk Weighted Assets		0.1263	0.1417
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		$ 746,140	$ 715,492
Tier 1 Capital Required for Capital Adequacy Purposes		$ 326,809	$ 278,155
Tier 1 Capital (to Risk Weighted Assets) Ratios
Tier 1 Capital to Risk Weighted Assets		0.1370	0.1543
Tier 1 Capital Required for Capital Adequacy Purposes to Risk Weighted Assets		0.0600	0.0600
Total Capital (to Risk Weighted Assets)
Total Capital		$ 877,281	$ 841,300
Total Capital Required for Capital Adequacy Purposes		$ 435,746	$ 370,874
Total Capital (to Risk Weighted Assets) Ratios
Total Capital to Risk Weighted Assets		0.1611	0.1815
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]	$ 746,140	$ 715,492
Tier 1 Capital Required for Capital Adequacy Purposes	[1]	$ 299,511	$ 277,065
Tier 1 Capital (to Average Assets) Ratios
Tier 1 Capital to Average Assets	[1]	0.0996	0.1033
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		$ 823,323	$ 793,271
Common Equity Tier 1 Capital for Capital Adequacy Purposes		245,085	208,576
Common Equity Tier 1 Capital to be Well Capitalized		$ 354,012	$ 301,277
Common Equity Tier 1 (to Risk Weighted Assets) Ratios [Abstract]
Common Equity Tier 1 Capital to Risk Weighted Assets		0.1512	0.1711
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		$ 823,323	$ 793,271
Tier 1 Capital Required for Capital Adequacy Purposes		326,780	278,102
Tier 1 Capital Required to be Well Capitalized		$ 435,707	$ 370,803
Tier 1 Capital (to Risk Weighted Assets) Ratios
Tier 1 Capital to Risk Weighted Assets		0.1512	0.1711
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		$ 855,790	$ 820,545
Total Capital Required for Capital Adequacy Purposes		435,707	370,803
Total Capital Required to be Well Capitalized		$ 544,633	$ 463,503
Total Capital (to Risk Weighted Assets) Ratios
Total Capital to Risk Weighted Assets		0.1571	0.1770
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]	$ 823,323	$ 793,271
Tier 1 Capital Required for Capital Adequacy Purposes	[1]	299,410	276,932
Tier 1 Capital Required to be Well Capitalized	[1]	$ 374,263	$ 346,165
Tier 1 Capital (to Average Assets) Ratios
Tier 1 Capital to Average Assets	[1]	0.1100	0.1146
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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