SEGMENT INFORMATION (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017 USD ($)	Sep. 30, 2016 USD ($)	Sep. 30, 2017 USD ($) segment	Sep. 30, 2016 USD ($)	Dec. 31, 2016 USD ($)
Segment Disclosure information
Number of reportable segments | segment			5
Segment information
Net interest income	$ 48,307	$ 39,398	$ 147,882	$ 114,409
Provision for loan and lease losses	4,221	2,489	21,633	9,489
Net refund transfer fees	177	132	18,329	19,119
Mortgage banking income	1,102	3,081	3,707	5,902
Program fees	1,597	979	3,972	1,942
Other noninterest income	7,498	7,109	22,216	20,061
Total noninterest income	10,374	11,301	48,224	47,024
Total noninterest expenses	38,026	33,534	112,699	97,941
Income before income tax expense	16,434	14,676	61,774	54,003
Income tax expense (benefit)	5,728	4,848	20,980	18,100
NET INCOME	10,706	9,828	40,794	35,903
Segment end of period assets	$ 4,993,174	$ 4,827,277	$ 4,993,174	$ 4,827,277	$ 4,816,309
Net interest margin (as percent)	4.17%	3.65%	4.34%	3.62%
Core Banking Activities
Segment Disclosure information
Number of reportable segments | segment			3
Segment information
Net interest income	$ 42,235	$ 36,134	$ 116,818	$ 100,796
Provision for loan and lease losses	609	477	2,575	2,253
Mortgage banking income	1,102	3,081	3,707	5,902
Other noninterest income	7,206	6,960	20,837	19,606
Total noninterest income	8,308	10,041	24,544	25,508
Total noninterest expenses	34,277	30,850	99,347	87,284
Income before income tax expense	15,657	14,848	39,440	36,767
Income tax expense (benefit)	5,446	4,910	12,875	11,847
NET INCOME	10,211	9,938	26,565	24,920
Segment end of period assets	$ 4,941,662	$ 4,784,877	$ 4,941,662	$ 4,784,877
Net interest margin (as percent)	3.68%	3.38%	3.49%	3.26%
Traditional Banking
Segment information
Net interest income	$ 37,396	$ 31,134	$ 103,490	$ 89,279
Provision for loan and lease losses	683	289	2,611	1,567
Other noninterest income	7,130	6,899	20,618	19,380
Total noninterest income	7,130	6,899	20,618	19,380
Total noninterest expenses	32,280	28,939	93,552	81,551
Income before income tax expense	11,563	8,805	27,945	25,541
Income tax expense (benefit)	3,951	2,707	8,684	7,733
NET INCOME	7,612	6,098	19,261	17,808
Segment end of period assets	$ 4,361,591	$ 4,109,464	$ 4,361,591	$ 4,109,464
Net interest margin (as percent)	3.70%	3.35%	3.48%	3.22%
Warehouse Lending
Segment information
Net interest income	$ 4,737	$ 4,924	$ 13,073	$ 11,369
Provision for loan and lease losses	(74)	188	(36)	686
Other noninterest income	11	4	27	14
Total noninterest income	11	4	27	14
Total noninterest expenses	848	727	2,448	2,157
Income before income tax expense	3,974	4,013	10,688	8,540
Income tax expense (benefit)	1,454	1,493	3,909	3,174
NET INCOME	2,520	2,520	6,779	5,366
Segment end of period assets	$ 570,676	$ 660,410	$ 570,676	$ 660,410
Net interest margin (as percent)	3.54%	3.63%	3.58%	3.64%
Mortgage Banking
Segment information
Net interest income	$ 102	$ 76	$ 255	$ 148
Mortgage banking income	1,102	3,081	3,707	5,902
Other noninterest income	65	57	192	212
Total noninterest income	1,167	3,138	3,899	6,114
Total noninterest expenses	1,149	1,184	3,347	3,576
Income before income tax expense	120	2,030	807	2,686
Income tax expense (benefit)	41	710	282	940
NET INCOME	79	1,320	525	1,746
Segment end of period assets	9,395	15,003	$ 9,395	15,003
Republic Processing Group
Segment Disclosure information
Number of reportable segments | segment			2
Segment information
Net interest income	6,072	3,264	$ 31,064	13,613
Provision for loan and lease losses	3,612	2,012	19,058	7,236
Net refund transfer fees	177	132	18,329	19,119
Program fees	1,597	979	3,972	1,942
Other noninterest income	292	149	1,379	455
Total noninterest income	2,066	1,260	23,680	21,516
Total noninterest expenses	3,749	2,684	13,352	10,657
Income before income tax expense	777	(172)	22,334	17,236
Income tax expense (benefit)	282	(62)	8,105	6,253
NET INCOME	495	(110)	14,229	10,983
Segment end of period assets	51,512	42,400	51,512	42,400
Tax Refund Solutions
Segment information
Net interest income	60	38	15,179	6,589
Provision for loan and lease losses	(840)	(89)	6,763	2,905
Net refund transfer fees	177	132	18,329	19,119
Program fees	63	29	103	174
Other noninterest income	16	13	152	176
Total noninterest income	256	174	18,584	19,469
Total noninterest expenses	2,851	2,075	10,891	9,029
Income before income tax expense	(1,695)	(1,774)	16,109	14,124
Income tax expense (benefit)	(615)	(642)	5,846	5,125
NET INCOME	(1,080)	(1,132)	10,263	8,999
Segment end of period assets	13,090	26,608	13,090	26,608
Republic Credit Solutions
Segment information
Net interest income	6,012	3,226	15,885	7,024
Provision for loan and lease losses	4,452	2,101	12,295	4,331
Program fees	1,534	950	3,869	1,768
Other noninterest income	276	136	1,227	279
Total noninterest income	1,810	1,086	5,096	2,047
Total noninterest expenses	898	609	2,461	1,628
Income before income tax expense	2,472	1,602	6,225	3,112
Income tax expense (benefit)	897	580	2,259	1,128
NET INCOME	1,575	1,022	3,966	1,984
Segment end of period assets	$ 38,422	$ 15,792	$ 38,422	$ 15,792