LOANS AND ALLOWANCE FOR LOAN AND LEASE LOSSES - DELINQUENT LOANS (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Aging or recorded investments in loans
Total Loans Delinquent	$ 25,833	$ 14,101
Total Loans Not Delinquent	4,026,667	3,999,933
Carrying value of loans	$ 4,052,500	$ 4,014,034
Delinquent acquired bank loans to total acquired bank loans (as a percent)	0.64%	0.35%
30 - 59 Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	$ 18,828	$ 7,833
Delinquent acquired bank loans to total acquired bank loans (as a percent)	0.46%	0.20%
60 - 89 Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	$ 2,674	$ 2,353
Delinquent acquired bank loans to total acquired bank loans (as a percent)	0.07%	0.06%
90 + Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	$ 4,331	$ 3,915
Delinquent acquired bank loans to total acquired bank loans (as a percent)	0.11%	0.10%
Core Banking Activities
Aging or recorded investments in loans
Total Loans Delinquent	$ 8,303	$ 8,460
Total Loans Not Delinquent	3,966,001	3,927,038
Carrying value of loans	3,974,304	3,935,498
Core Banking Activities | 30 - 59 Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	3,178	4,202
Core Banking Activities | 60 - 89 Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	2,046	1,280
Core Banking Activities | 90 + Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	3,079	2,978
Traditional Banking
Aging or recorded investments in loans
Total Loans Delinquent	8,303	8,460
Total Loans Not Delinquent	3,432,042	3,401,466
Carrying value of loans	3,440,345	3,409,926
Traditional Banking | 30 - 59 Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	3,178	4,202
Traditional Banking | 60 - 89 Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	2,046	1,280
Traditional Banking | 90 + Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	3,079	2,978
Republic Processing Group
Aging or recorded investments in loans
Total Loans Delinquent	17,530	5,641
Total Loans Not Delinquent	60,666	72,895
Carrying value of loans	78,196	78,536
Republic Processing Group | 30 - 59 Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	15,650	3,631
Republic Processing Group | 60 - 89 Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	628	1,073
Republic Processing Group | 90 + Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	1,252	937
Residential Real Estate - Owner Occupied | Traditional Banking
Aging or recorded investments in loans
Total Loans Delinquent	3,495	4,782
Total Loans Not Delinquent	908,920	916,783
Carrying value of loans	912,415	921,565
Residential Real Estate - Owner Occupied | Traditional Banking | 30 - 59 Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	1,191	2,559
Residential Real Estate - Owner Occupied | Traditional Banking | 60 - 89 Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	960	1,166
Residential Real Estate - Owner Occupied | Traditional Banking | 90 + Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	1,344	1,057
Residential Real Estate - Owner Occupied - Correspondent | Traditional Banking
Aging or recorded investments in loans
Total Loans Delinquent	383
Total Loans Not Delinquent	110,880	116,792
Carrying value of loans	111,263	116,792
Residential Real Estate - Owner Occupied - Correspondent | Traditional Banking | 30 - 59 Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	383
Residential Real Estate - Non Owner Occupied | Traditional Banking
Aging or recorded investments in loans
Total Loans Delinquent	744	146
Total Loans Not Delinquent	215,351	204,935
Carrying value of loans	216,095	205,081
Residential Real Estate - Non Owner Occupied | Traditional Banking | 30 - 59 Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	645	47
Residential Real Estate - Non Owner Occupied | Traditional Banking | 90 + Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	99	99
Commercial Real Estate | Traditional Banking
Aging or recorded investments in loans
Total Loans Delinquent	2,290	1,727
Total Loans Not Delinquent	1,214,302	1,205,566
Carrying value of loans	1,216,592	1,207,293
Commercial Real Estate | Traditional Banking | 30 - 59 Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	80	398
Commercial Real Estate | Traditional Banking | 60 - 89 Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	811
Commercial Real Estate | Traditional Banking | 90 + Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	1,399	1,329
Construction & land development | Traditional Banking
Aging or recorded investments in loans
Total Loans Delinquent		67
Total Loans Not Delinquent	160,391	149,998
Carrying value of loans	160,391	150,065
Construction & land development | Traditional Banking | 30 - 59 Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent		67
Commercial & industrial | Traditional Banking
Aging or recorded investments in loans
Total Loans Delinquent	139	15
Total Loans Not Delinquent	355,177	341,677
Carrying value of loans	355,316	341,692
Commercial & industrial | Traditional Banking | 30 - 59 Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	124	15
Commercial & industrial | Traditional Banking | 60 - 89 Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	15
Lease Financing Receivables | Traditional Banking
Aging or recorded investments in loans
Total Loans Not Delinquent	15,751	16,580
Carrying value of loans	15,751	16,580
Home equity lines of credit | Traditional Banking
Aging or recorded investments in loans
Total Loans Delinquent	847	1,221
Total Loans Not Delinquent	341,370	346,434
Carrying value of loans	342,217	347,655
Home equity lines of credit | Traditional Banking | 30 - 59 Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	481	723
Home equity lines of credit | Traditional Banking | 60 - 89 Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	179	50
Home equity lines of credit | Traditional Banking | 90 + Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	187	448
Consumer: Credit cards | Traditional Banking
Aging or recorded investments in loans
Total Loans Delinquent	67	74
Total Loans Not Delinquent	16,610	16,004
Carrying value of loans	16,677	16,078
Consumer: Credit cards | Traditional Banking | 30 - 59 Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	37	34
Consumer: Credit cards | Traditional Banking | 60 - 89 Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	29	40
Consumer: Credit cards | Traditional Banking | 90 + Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	1
Consumer: Overdrafts | Traditional Banking
Aging or recorded investments in loans
Total Loans Delinquent	177	233
Total Loans Not Delinquent	614	741
Carrying value of loans	791	974
Consumer: Overdrafts | Traditional Banking | 30 - 59 Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	176	230
Consumer: Overdrafts | Traditional Banking | 60 - 89 Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	1	3
Consumer: Automobile loan | Traditional Banking
Aging or recorded investments in loans
Total Loans Delinquent	44	60
Total Loans Not Delinquent	65,237	65,590
Carrying value of loans	65,281	65,650
Consumer: Automobile loan | Traditional Banking | 30 - 59 Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent		36
Consumer: Automobile loan | Traditional Banking | 60 - 89 Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	21
Consumer: Automobile loan | Traditional Banking | 90 + Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	23	24
Other consumer | Traditional Banking
Aging or recorded investments in loans
Total Loans Delinquent	117	135
Total Loans Not Delinquent	27,439	20,366
Carrying value of loans	27,556	20,501
Other consumer | Traditional Banking | 30 - 59 Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	61	93
Other consumer | Traditional Banking | 60 - 89 Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	30	21
Other consumer | Traditional Banking | 90 + Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	26	21
Warehouse lines of credit | Core Banking Activities
Aging or recorded investments in loans
Total Loans Not Delinquent	533,959	525,572
Carrying value of loans	533,959	525,572
Easy Advances | Republic Processing Group
Aging or recorded investments in loans
Total Loans Delinquent	13,163
Total Loans Not Delinquent	2,438
Carrying value of loans	15,601
Easy Advances | Republic Processing Group | 30 - 59 Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	13,163
Other TRS loans | Republic Processing Group
Aging or recorded investments in loans
Total Loans Not Delinquent	192	11,648
Carrying value of loans	192	11,648
Republic Credit Solutions | Republic Processing Group
Aging or recorded investments in loans
Total Loans Delinquent	4,367	5,641
Total Loans Not Delinquent	58,036	61,247
Carrying value of loans	62,403	66,888
Republic Credit Solutions | Republic Processing Group | 30 - 59 Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	2,487	3,631
Republic Credit Solutions | Republic Processing Group | 60 - 89 Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	628	1,073
Republic Credit Solutions | Republic Processing Group | 90 + Days Delinquent
Aging or recorded investments in loans
Total Loans Delinquent	$ 1,252	$ 937