LOANS AND ALLOWANCE FOR CREDIT LOSSES - COMPOSITION OF LOANS (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018
Loans disclosures
Total loans	$ 5,065,092		$ 4,433,151
Allowance for loan and lease losses	(55,097)	$ (70,431)	(43,351)	$ (45,983)	$ (57,961)	$ (44,675)
Loans, net	5,009,995		4,389,800
Core Banking
Loans disclosures
Total loans	4,965,602		4,313,389
Allowance for loan and lease losses	(45,752)	(42,680)	(29,999)	(32,983)	(31,569)	(31,519)
Traditional Banking
Loans disclosures
Total loans	3,935,823		3,595,931
Allowance for loan and lease losses	(43,177)	(40,554)	(28,205)	(31,169)	(30,172)	(30,347)
Republic Processing Group
Loans disclosures
Total loans	99,490		119,762
Allowance for loan and lease losses	(9,345)	(27,751)	(13,352)	(13,000)	(26,392)	(13,156)
PPP Loans | Traditional Banking
Loans disclosures
Total loans	511,065
Residential Real Estate - Owner Occupied
Loans disclosures
Total loans	885,325
Residential Real Estate - Owner Occupied | Traditional Banking
Loans disclosures
Total loans	885,325		949,568
Allowance for loan and lease losses	(9,303)	(9,387)	(4,729)	(5,213)	(5,801)	(6,035)
Residential Real Estate - Non Owner Occupied
Loans disclosures
Total loans	254,700
Residential Real Estate - Non Owner Occupied | Traditional Banking
Loans disclosures
Total loans	254,700		258,803
Allowance for loan and lease losses	(2,274)	(2,165)	(1,737)	(1,775)	(1,720)	(1,662)
Commercial Real Estate
Loans disclosures
Total loans	1,322,290
Commercial Real Estate | Traditional Banking
Loans disclosures
Total loans	1,322,290		1,303,000
Allowance for loan and lease losses	(16,300)	(13,381)	(10,486)	(10,566)	(10,235)	(10,030)
Construction & land development
Loans disclosures
Total loans	157,254
Construction & land development | Traditional Banking
Loans disclosures
Total loans	157,254		159,702
Allowance for loan and lease losses	(4,940)	(4,536)	(2,152)	(2,910)	(2,443)	(2,555)
Commercial & industrial
Loans disclosures
Total loans	904,727
Commercial & industrial | Traditional Banking
Loans disclosures
Total loans	904,727		477,236
Allowance for loan and lease losses	(2,405)	(2,541)	(2,882)	(4,221)	(3,235)	(2,873)
Commercial & industrial | PPP Loans | Traditional Banking
Loans disclosures
Total loans	511,065
Lease Financing Receivables
Loans disclosures
Total loans	11,864
Lease Financing Receivables | Traditional Banking
Loans disclosures
Total loans	11,864		14,040
Allowance for loan and lease losses	(125)	(133)	(147)	(181)	(150)	(158)
Home equity lines of credit
Loans disclosures
Total loans	265,266
Home equity lines of credit | Traditional Banking
Loans disclosures
Total loans	265,266		293,186
Allowance for loan and lease losses	(5,124)	(5,290)	(2,721)	(3,124)	(3,337)	(3,477)
Consumer: Credit cards | Traditional Banking
Loans disclosures
Total loans	14,265		17,836
Allowance for loan and lease losses	(928)	(978)	(1,020)	(1,028)	(1,079)	(1,140)
Consumer: Overdrafts | Traditional Banking
Loans disclosures
Total loans	488		1,522
Allowance for loan and lease losses	(488)	(758)	(1,169)	(894)	(892)	(1,102)
Consumer: Automobile loan | Traditional Banking
Loans disclosures
Total loans	41,059		52,923
Allowance for loan and lease losses	(473)	(546)	(612)	(708)	(768)	(724)
Consumer
Loans disclosures
Total loans	134,397
Consumer | Traditional Banking
Loans disclosures
Total loans	134,397
Other consumer | Traditional Banking
Loans disclosures
Total loans	78,585		68,115
Allowance for loan and lease losses	(817)	(839)	(550)	(549)	(512)	(591)
Warehouse lines of credit
Loans disclosures
Total loans	1,029,779
Warehouse lines of credit | Core Banking
Loans disclosures
Total loans	1,029,779		717,458
Allowance for loan and lease losses	(2,575)	(2,126)	(1,794)	(1,814)	(1,397)	(1,172)
Easy Advances | Republic Processing Group
Loans disclosures
Allowance for loan and lease losses		(15,270)			(13,381)
Other TRS loans
Loans disclosures
Total loans	289
Other TRS loans | Republic Processing Group
Loans disclosures
Total loans	289		14,365
Allowance for loan and lease losses	(211)	(95)	(234)	(232)	(149)	(107)
Republic Credit Solutions
Loans disclosures
Total loans	99,201
Republic Credit Solutions | Republic Processing Group
Loans disclosures
Total loans	99,201		105,397
Allowance for loan and lease losses	$ (9,134)	$ (12,386)	$ (13,118)	$ (12,768)	$ (12,862)	$ (13,049)