GOODWILL AND CORE DEPOSIT INTANGIBLES (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017	Sep. 30, 2018
Goodwill
Beginning of period			$ 85,291	$ 85,291	$ 85,291
End of the period	$ 85,291		85,291		85,291
Core Deposit Intangibles
Beginning of period			8,503	9,975	9,975
Less amortization			(919)	(1,140)	(1,472)
End of period	7,584		7,584		8,503
Amortization of intangible assets			919	1,140	1,472
Expected future amortization expense
Total	7,584		8,503	$ 9,975	$ 9,975	$ 7,584
Core deposit intangibles
Core Deposit Intangibles
Less amortization	(297)	$ (380)
End of period	7,584		7,584
Amortization of intangible assets	297	$ 380
Expected future amortization expense
2018						276
2019						1,080
2020						993
2021						905
2022						818
Thereafter						3,512
Total	$ 7,584		$ 7,584			$ 7,584
Core deposit intangibles | Minimum
Core Deposit Intangibles
Intangible asset useful life			6 years
Core deposit intangibles | Maximum
Core Deposit Intangibles
Intangible asset useful life			19 years