LOANS AND ALLOWANCE FOR LOAN AND LEASE LOSSES - COMPOSITION OF LOANS (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017	Mar. 31, 2017	Dec. 31, 2016
Loans disclosures
Total loans	$ 4,052,500	$ 4,014,034
Allowance for loan and lease losses	(52,341)	(42,769)	$ (42,362)	$ (32,920)
Loans, net	4,000,159	3,971,265
Core Banking Activities
Loans disclosures
Total loans	3,974,304	3,935,498
Allowance for loan and lease losses	(30,566)	(30,147)	(27,990)	(27,928)
Traditional Banking
Loans disclosures
Total loans	3,440,345	3,409,926
Allowance for loan and lease losses	(29,231)	(28,833)	(26,752)	(26,464)
Republic Processing Group
Loans disclosures
Total loans	78,196	78,536
Allowance for loan and lease losses	(21,775)	(12,622)	(14,372)	(4,992)
Residential Real Estate - Owner Occupied | Traditional Banking
Loans disclosures
Total loans	912,415	921,565
Allowance for loan and lease losses	(5,988)	(6,182)	(7,071)	(7,158)
Residential Real Estate - Owner Occupied - Correspondent | Traditional Banking
Loans disclosures
Total loans	111,263	116,792
Allowance for loan and lease losses	(278)	(292)	(353)	(373)
Residential Real Estate - Non Owner Occupied | Traditional Banking
Loans disclosures
Total loans	216,095	205,081
Allowance for loan and lease losses	(1,461)	(1,396)	(1,198)	(1,139)
Commercial Real Estate | Traditional Banking
Loans disclosures
Total loans	1,216,592	1,207,293
Allowance for loan and lease losses	(9,460)	(9,043)	(7,898)	(8,078)
Construction & land development | Traditional Banking
Loans disclosures
Total loans	160,391	150,065
Allowance for loan and lease losses	(2,720)	(2,364)	(2,233)	(1,850)
Commercial & industrial | Traditional Banking
Loans disclosures
Total loans	355,316	341,692
Allowance for loan and lease losses	(2,247)	(2,198)	(1,488)	(1,511)
Lease Financing Receivables | Traditional Banking
Loans disclosures
Total loans	15,751	16,580
Allowance for loan and lease losses	(165)	(174)	(145)	(136)
Home equity lines of credit | Traditional Banking
Loans disclosures
Total loans	342,217	347,655
Allowance for loan and lease losses	(3,669)	(3,754)	(3,831)	(3,757)
Consumer: Credit cards | Traditional Banking
Loans disclosures
Total loans	16,677	16,078
Allowance for loan and lease losses	(756)	(607)	(506)	(490)
Consumer: Overdrafts | Traditional Banking
Loans disclosures
Total loans	791	974
Allowance for loan and lease losses	(791)	(974)	(641)	(675)
Consumer: Automobile loan | Traditional Banking
Loans disclosures
Total loans	65,281	65,650
Allowance for loan and lease losses	(706)	(687)	(563)	(526)
Other consumer | Traditional Banking
Loans disclosures
Total loans	27,556	20,501
Allowance for loan and lease losses	(990)	(1,162)	(825)	(771)
Warehouse lines of credit | Core Banking Activities
Loans disclosures
Total loans	533,959	525,572
Allowance for loan and lease losses	(1,335)	(1,314)	(1,238)	(1,464)
Easy Advances | Republic Processing Group
Loans disclosures
Total loans	15,601
Allowance for loan and lease losses	(9,572)		(7,741)
Other TRS loans | Republic Processing Group
Loans disclosures
Total loans	192	11,648
Allowance for loan and lease losses	(125)	(12)		(25)
Republic Credit Solutions | Republic Processing Group
Loans disclosures
Total loans	62,403	66,888
Allowance for loan and lease losses	$ (12,078)	$ (12,610)	$ (6,631)	$ (4,967)