SEGMENT INFORMATION (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2016 USD ($) segment	Mar. 31, 2015 USD ($)	Dec. 31, 2015 USD ($)
Segment Disclosure information
Number of operating segments | segment	4
Segment information
Net interest income	$ 39,434	$ 29,022
Provision for loan and lease losses	5,186	185
Net refund transfer fees	17,078	15,335
Mortgage banking income	1,261	1,353
Republic Processing Group program fees	319	228
Other non interest income	6,263	6,070
Total noninterest income	24,921	22,986
Total non interest expenses	32,541	31,074
INCOME BEFORE INCOME TAX EXPENSE	26,628	20,749
Income tax expense (benefit)	8,893	6,961
NET INCOME	17,735	13,788
Segment end of period total assets	$ 4,246,765	$ 3,952,187	$ 4,230,289
Net interest margin (as percent)	3.78%	3.14%
Traditional Banking
Segment information
Net interest income	$ 28,608	$ 25,758
Provision for loan and lease losses	480	116
Other non interest income	6,110	5,397
Total noninterest income	6,110	5,397
Total non interest expenses	24,875	23,407
INCOME BEFORE INCOME TAX EXPENSE	9,363	7,632
Income tax expense (benefit)	2,613	2,286
NET INCOME	6,750	5,346
Segment end of period total assets	$ 3,711,315	$ 3,380,813
Net interest margin (as percent)	3.08%	3.13%
Warehouse Lending
Segment information
Net interest income	$ 2,655	$ 2,541
Provision for loan and lease losses	18	259
Other non interest income	5	5
Total noninterest income	5	5
Total non interest expenses	695	573
INCOME BEFORE INCOME TAX EXPENSE	1,947	1,714
Income tax expense (benefit)	723	600
NET INCOME	1,224	1,114
Segment end of period total assets	$ 393,532	$ 422,652
Net interest margin (as percent)	3.63%	3.62%
Mortgage Banking
Segment information
Net interest income	$ 32	$ 56
Mortgage banking income	1,261	1,353
Other non interest income	92	84
Total noninterest income	1,353	1,437
Total non interest expenses	1,240	1,285
INCOME BEFORE INCOME TAX EXPENSE	145	208
Income tax expense (benefit)	51	73
NET INCOME	94	135
Segment end of period total assets	$ 12,965	18,002
Core Banking Activities
Segment Disclosure information
Number of operating segments | segment	3
Segment information
Net interest income	$ 31,295	28,355
Provision for loan and lease losses	498	375
Mortgage banking income	1,261	1,353
Other non interest income	6,207	5,486
Total noninterest income	7,468	6,839
Total non interest expenses	26,810	25,265
INCOME BEFORE INCOME TAX EXPENSE	11,455	9,554
Income tax expense (benefit)	3,387	2,959
NET INCOME	8,068	6,595
Segment end of period total assets	$ 4,117,812	$ 3,821,467
Net interest margin (as percent)	3.12%	3.17%
Republic Processing Group
Segment information
Net interest income	$ 8,139	$ 667
Provision for loan and lease losses	4,688	(190)
Net refund transfer fees	17,078	15,335
Republic Processing Group program fees	319	228
Other non interest income	56	584
Total noninterest income	17,453	16,147
Total non interest expenses	5,731	5,809
INCOME BEFORE INCOME TAX EXPENSE	15,173	11,195
Income tax expense (benefit)	5,506	4,002
NET INCOME	9,667	7,193
Segment end of period total assets	$ 128,953	$ 130,720