LOANS AND ALLOWANCE FOR CREDIT LOSSES - DELINQUENT LOANS (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Aging or recorded investments in loans
Total Loans Delinquent	$ 14,046	$ 20,804
Total Loans Not Delinquent	5,051,046	4,412,347
Carrying value of loans	$ 5,065,092	$ 4,433,151
Delinquent acquired bank loans to total acquired bank loans (as a percent)	0.28%	0.47%
30 - 59 Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	$ 6,391	$ 10,090
Delinquent acquired bank loans to total acquired bank loans (as a percent)	0.13%	0.23%
60 - 89 Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	$ 2,407	$ 3,063
Delinquent acquired bank loans to total acquired bank loans (as a percent)	0.05%	0.07%
90 + Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	$ 5,248	$ 7,651
Delinquent acquired bank loans to total acquired bank loans (as a percent)	0.10%	0.17%
Core Banking
Aging or recorded investments in loans
Total Loans Delinquent	$ 7,861	$ 13,042
Total Loans Not Delinquent	4,957,741	4,300,347
Carrying value of loans	4,965,602	4,313,389
Core Banking | 30 - 59 Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	2,020	4,001
Core Banking | 60 - 89 Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	1,128	1,547
Core Banking | 90 + Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	4,713	7,494
Traditional Banking
Aging or recorded investments in loans
Total Loans Delinquent	7,861	13,042
Total Loans Not Delinquent	3,927,962	3,582,889
Carrying value of loans	3,935,823	3,595,931
Traditional Banking | 30 - 59 Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	2,020	4,001
Traditional Banking | 60 - 89 Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	1,128	1,547
Traditional Banking | 90 + Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	4,713	7,494
Republic Processing Group
Aging or recorded investments in loans
Total Loans Delinquent	6,185	7,762
Total Loans Not Delinquent	93,305	112,000
Carrying value of loans	99,490	119,762
Republic Processing Group | 30 - 59 Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	4,371	6,089
Republic Processing Group | 60 - 89 Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	1,279	1,516
Republic Processing Group | 90 + Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	535	157
Residential Real Estate - Owner Occupied
Aging or recorded investments in loans
Carrying value of loans	885,325
Residential Real Estate - Owner Occupied | Traditional Banking
Aging or recorded investments in loans
Total Loans Delinquent	4,214	4,434
Total Loans Not Delinquent	881,111	945,134
Carrying value of loans	885,325	949,568
Residential Real Estate - Owner Occupied | Traditional Banking | 30 - 59 Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	1,527	1,460
Residential Real Estate - Owner Occupied | Traditional Banking | 60 - 89 Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	576	1,153
Residential Real Estate - Owner Occupied | Traditional Banking | 90 + Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	2,111	1,821
Residential Real Estate - Non Owner Occupied
Aging or recorded investments in loans
Carrying value of loans	254,700
Residential Real Estate - Non Owner Occupied | Traditional Banking
Aging or recorded investments in loans
Total Loans Delinquent	539	539
Total Loans Not Delinquent	254,161	258,264
Carrying value of loans	254,700	258,803
Residential Real Estate - Non Owner Occupied | Traditional Banking | 90 + Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	539	539
Commercial Real Estate
Aging or recorded investments in loans
Carrying value of loans	1,322,290
Commercial Real Estate | Traditional Banking
Aging or recorded investments in loans
Total Loans Delinquent	543	3,300
Total Loans Not Delinquent	1,321,747	1,299,700
Carrying value of loans	1,322,290	1,303,000
Commercial Real Estate | Traditional Banking | 30 - 59 Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent		155
Commercial Real Estate | Traditional Banking | 90 + Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	543	3,145
Construction & land development
Aging or recorded investments in loans
Carrying value of loans	157,254
Construction & land development | Traditional Banking
Aging or recorded investments in loans
Total Loans Not Delinquent	157,254	159,702
Carrying value of loans	157,254	159,702
Commercial & industrial
Aging or recorded investments in loans
Carrying value of loans	904,727
Commercial & industrial | Traditional Banking
Aging or recorded investments in loans
Total Loans Delinquent	1,362	1,355
Total Loans Not Delinquent	903,365	475,881
Carrying value of loans	904,727	477,236
Commercial & industrial | Traditional Banking | 30 - 59 Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent		200
Commercial & industrial | Traditional Banking | 60 - 89 Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	490	128
Commercial & industrial | Traditional Banking | 90 + Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	872	1,027
Lease Financing Receivables
Aging or recorded investments in loans
Carrying value of loans	11,864
Lease Financing Receivables | Traditional Banking
Aging or recorded investments in loans
Total Loans Not Delinquent	11,864	14,040
Carrying value of loans	11,864	14,040
Home equity lines of credit
Aging or recorded investments in loans
Carrying value of loans	265,266
Home equity lines of credit | Traditional Banking
Aging or recorded investments in loans
Total Loans Delinquent	1,053	2,918
Total Loans Not Delinquent	264,213	290,268
Carrying value of loans	265,266	293,186
Home equity lines of credit | Traditional Banking | 30 - 59 Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	397	1,810
Home equity lines of credit | Traditional Banking | 60 - 89 Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	23	166
Home equity lines of credit | Traditional Banking | 90 + Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	633	942
Consumer: Credit cards | Traditional Banking
Aging or recorded investments in loans
Total Loans Delinquent	7	155
Total Loans Not Delinquent	14,258	17,681
Carrying value of loans	14,265	17,836
Consumer: Credit cards | Traditional Banking | 30 - 59 Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	2	80
Consumer: Credit cards | Traditional Banking | 60 - 89 Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	5	75
Consumer: Overdrafts | Traditional Banking
Aging or recorded investments in loans
Total Loans Delinquent	94	283
Total Loans Not Delinquent	394	1,239
Carrying value of loans	488	1,522
Consumer: Overdrafts | Traditional Banking | 30 - 59 Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	91	278
Consumer: Overdrafts | Traditional Banking | 60 - 89 Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	3	4
Consumer: Overdrafts | Traditional Banking | 90 + Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent		1
Consumer: Automobile loan | Traditional Banking
Aging or recorded investments in loans
Total Loans Delinquent	27	49
Total Loans Not Delinquent	41,032	52,874
Carrying value of loans	41,059	52,923
Consumer: Automobile loan | Traditional Banking | 30 - 59 Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent		16
Consumer: Automobile loan | Traditional Banking | 60 - 89 Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	12	15
Consumer: Automobile loan | Traditional Banking | 90 + Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	15	18
Consumer
Aging or recorded investments in loans
Carrying value of loans	134,397
Consumer | Traditional Banking
Aging or recorded investments in loans
Carrying value of loans	134,397
Other consumer | Traditional Banking
Aging or recorded investments in loans
Total Loans Delinquent	22	9
Total Loans Not Delinquent	78,563	68,106
Carrying value of loans	78,585	68,115
Other consumer | Traditional Banking | 30 - 59 Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	3	2
Other consumer | Traditional Banking | 60 - 89 Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	19	6
Other consumer | Traditional Banking | 90 + Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent		1
Warehouse lines of credit
Aging or recorded investments in loans
Carrying value of loans	1,029,779
Warehouse lines of credit | Core Banking
Aging or recorded investments in loans
Total Loans Not Delinquent	1,029,779	717,458
Carrying value of loans	1,029,779	717,458
Other TRS loans
Aging or recorded investments in loans
Carrying value of loans	289
Other TRS loans | Republic Processing Group
Aging or recorded investments in loans
Total Loans Delinquent	259	119
Total Loans Not Delinquent	30	14,246
Carrying value of loans	289	14,365
Other TRS loans | Republic Processing Group | 30 - 59 Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent		35
Other TRS loans | Republic Processing Group | 60 - 89 Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	77	31
Other TRS loans | Republic Processing Group | 90 + Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	182	53
Republic Credit Solutions
Aging or recorded investments in loans
Carrying value of loans	99,201
Republic Credit Solutions | Republic Processing Group
Aging or recorded investments in loans
Total Loans Delinquent	5,926	7,643
Total Loans Not Delinquent	93,275	97,754
Carrying value of loans	99,201	105,397
Republic Credit Solutions | Republic Processing Group | 30 - 59 Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	4,371	6,054
Republic Credit Solutions | Republic Processing Group | 60 - 89 Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	1,202	1,485
Republic Credit Solutions | Republic Processing Group | 90 + Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	$ 353	$ 104