LOANS AND ALLOWANCE FOR LOAN AND LEASE LOSSES (Summary of Aging of the Loan Portfolio by Class) (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Financing Receivable, Recorded Investment, Past Due [Line Items]
Greater Than 90 Days and Still Accruing	$ 8,247	$ 9,132
Greater than 90 Days and still Accruing, % of total loans	0.06%	0.07%
Nonaccrual	$ 29,032	$ 31,100	$ 42,448
Nonaccrual, % of total loans	0.22%	0.24%
Total Loans	$ 13,459,349	$ 13,195,843
Total loans, % of total loans	100.00%	100.00%
Current
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable, current and past due	$ 13,400,748	$ 13,134,805
Current, % of total loans	99.56%	99.54%
30 to 59 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable, current and past due	$ 17,955	$ 15,094
Past Due, % of total loans	0.13%	0.11%
60 to 89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable, current and past due	$ 3,367	$ 5,712
Past Due, % of total loans	0.03%	0.04%
Construction and Land Development
Financing Receivable, Recorded Investment, Past Due [Line Items]
Greater Than 90 Days and Still Accruing	$ 1	$ 299
Nonaccrual	869	2,697	3,072
Total Loans	969,059	862,236
Construction and Land Development | Current
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable, current and past due	968,019	857,883
Construction and Land Development | 30 to 59 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable, current and past due	170	1,357
Construction and Land Development | 60 to 89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable, current and past due	0	0
Commercial Real Estate - Owner Occupied
Financing Receivable, Recorded Investment, Past Due [Line Items]
Greater Than 90 Days and Still Accruing	2,396	1,257
Nonaccrual	4,865	5,637	7,128
Total Loans	2,007,671	1,995,409
Commercial Real Estate - Owner Occupied | Current
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable, current and past due	1,995,329	1,987,133
Commercial Real Estate - Owner Occupied | 30 to 59 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable, current and past due	5,081	1,230
Commercial Real Estate - Owner Occupied | 60 to 89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable, current and past due	0	152
Commercial Real Estate - Non-Owner Occupied
Financing Receivable, Recorded Investment, Past Due [Line Items]
Greater Than 90 Days and Still Accruing	1,735	433
Nonaccrual	3,287	3,641	2,317
Total Loans	3,875,681	3,789,377
Commercial Real Estate - Non-Owner Occupied | Current
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable, current and past due	3,870,357	3,783,211
Commercial Real Estate - Non-Owner Occupied | 30 to 59 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable, current and past due	79	1,965
Commercial Real Estate - Non-Owner Occupied | 60 to 89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable, current and past due	223	127
Multifamily Real Estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Greater Than 90 Days and Still Accruing	0	0
Nonaccrual	0	113	33
Total Loans	723,940	778,626
Multifamily Real Estate | Current
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable, current and past due	723,816	778,429
Multifamily Real Estate | 30 to 59 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable, current and past due	124	84
Multifamily Real Estate | 60 to 89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable, current and past due	0	0
Commercial and Industrial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Greater Than 90 Days and Still Accruing	763	1,897
Nonaccrual	1,975	1,647	2,107
Total Loans	2,540,680	2,542,243
Commercial and Industrial | Current
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable, current and past due	2,535,815	2,536,100
Commercial and Industrial | 30 to 59 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable, current and past due	1,382	1,161
Commercial and Industrial | 60 to 89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable, current and past due	745	1,438
Residential 1-4 Family - Commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Greater Than 90 Days and Still Accruing	878	990
Nonaccrual	2,239	2,285	9,993
Total Loans	569,801	607,337
Residential 1-4 Family - Commercial | Current
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable, current and past due	565,606	601,946
Residential 1-4 Family - Commercial | 30 to 59 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable, current and past due	827	1,844
Residential 1-4 Family - Commercial | 60 to 89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable, current and past due	251	272
Residential 1-4 Family - Mortgage
Financing Receivable, Recorded Investment, Past Due [Line Items]
Greater Than 90 Days and Still Accruing	1,147	3,013
Nonaccrual	12,039	11,397	12,600
Total Loans	824,163	816,524
Residential 1-4 Family - Mortgage | Current
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable, current and past due	804,069	795,821
Total Loans	804,069	795,821
Residential 1-4 Family - Mortgage | 30 to 59 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable, current and past due	5,890	3,368
Total Loans	5,890	3,368
Residential 1-4 Family - Mortgage | 60 to 89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable, current and past due	1,018	2,925
Total Loans	1,018	2,925
Residential 1-4 Family - Mortgage | Greater Than 90 Days and still Accruing
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans	1,147	3,013
Residential 1-4 Family - Mortgage | Nonaccrual
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans	12,039	11,397
Residential 1-4 Family - Revolving
Financing Receivable, Recorded Investment, Past Due [Line Items]
Greater Than 90 Days and Still Accruing	1,065	882
Nonaccrual	3,371	3,406	4,629
Total Loans	568,403	560,796
Residential 1-4 Family - Revolving | Current
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable, current and past due	562,159	554,652
Total Loans	562,159	554,652
Residential 1-4 Family - Revolving | 30 to 59 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable, current and past due	1,157	1,493
Total Loans	1,157	1,493
Residential 1-4 Family - Revolving | 60 to 89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable, current and past due	651	363
Total Loans	651	363
Residential 1-4 Family - Revolving | Greater Than 90 Days and still Accruing
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans	1,065	882
Residential 1-4 Family - Revolving | Nonaccrual
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans	3,371	3,406
Auto
Financing Receivable, Recorded Investment, Past Due [Line Items]
Greater Than 90 Days and Still Accruing	192	241
Nonaccrual	333	223	500
Total Loans	499,855	461,052
Auto | Current
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable, current and past due	497,639	458,473
Total Loans	497,639	458,473
Auto | 30 to 59 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable, current and past due	1,508	1,866
Total Loans	1,508	1,866
Auto | 60 to 89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable, current and past due	183	249
Total Loans	183	249
Auto | Greater Than 90 Days and still Accruing
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans	192	241
Auto | Nonaccrual
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans	333	223
Consumer
Financing Receivable, Recorded Investment, Past Due [Line Items]
Greater Than 90 Days and Still Accruing	70	120
Nonaccrual	54	54	$ 69
Total Loans	171,875	176,992
Consumer | Current
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable, current and past due	171,083	175,943
Total Loans	171,083	175,943
Consumer | 30 to 59 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable, current and past due	467	689
Total Loans	467	689
Consumer | 60 to 89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable, current and past due	201	186
Total Loans	201	186
Consumer | Greater Than 90 Days and still Accruing
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans	70	120
Consumer | Nonaccrual
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans	54	54
Other Commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Greater Than 90 Days and Still Accruing	0	0
Nonaccrual	0	0
Total Loans	708,221	605,251
Other Commercial | Current
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable, current and past due	706,856	605,214
Other Commercial | 30 to 59 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable, current and past due	1,270	37
Other Commercial | 60 to 89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable, current and past due	$ 95	$ 0