SECURITIES - Securities Available for Sale (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Amortized cost and estimated fair value of securities available for sale [Abstract]
Amortized Cost	$ 274,852	$ 297,947
Unrealized Gains	118	514
Unrealized Losses	9,813	5,370
Securities available for sale	265,157	293,091
Amortized Cost [Abstract]
Within one year	16,875
After one, but within five years	19,459
After five, but within ten years	26,495
After ten years	483
Total	63,312
Amortized Cost	274,852	297,947
Fair Value [Abstract]
Within one year	16,873
After one, but within five years	19,347
After five, but within ten years	26,053
After ten years	456
Total	62,729
Estimated Fair Value	265,157	293,091
Obligations of U.S. Government and U.S. Government sponsored enterprises
Amortized cost and estimated fair value of securities available for sale [Abstract]
Amortized Cost	15,489	15,492
Unrealized Gains	11	20
Unrealized Losses	50	21
Securities available for sale	15,450	15,491
Amortized Cost [Abstract]
Amortized Cost	15,489	15,492
Fair Value [Abstract]
Estimated Fair Value	15,450	15,491
Mortgage-backed securities, residential
Amortized cost and estimated fair value of securities available for sale [Abstract]
Amortized Cost	207,708	224,939
Unrealized Gains	69	136
Unrealized Losses	9,137	5,166
Securities available for sale	198,640	219,909
Amortized Cost [Abstract]
Without single maturity date	207,708
Amortized Cost	207,708	224,939
Fair Value [Abstract]
Without single maturity date	198,640
Estimated Fair Value	198,640	219,909
Obligations of states and political subdivisions
Amortized cost and estimated fair value of securities available for sale [Abstract]
Amortized Cost	47,574	52,928
Unrealized Gains	37	355
Unrealized Losses	582	151
Securities available for sale	47,029	53,132
Amortized Cost [Abstract]
Amortized Cost	47,574	52,928
Fair Value [Abstract]
Estimated Fair Value	47,029	53,132
Corporate bonds and notes
Amortized cost and estimated fair value of securities available for sale [Abstract]
Amortized Cost	249	249
Unrealized Gains	1	2
Unrealized Losses	0	0
Securities available for sale	250	251
Amortized Cost [Abstract]
Amortized Cost	249	249
Fair Value [Abstract]
Estimated Fair Value	250	251
SBA loan pools
Amortized cost and estimated fair value of securities available for sale [Abstract]
Amortized Cost	3,832	4,339
Unrealized Gains	0	1
Unrealized Losses	44	32
Securities available for sale	3,788	4,308
Amortized Cost [Abstract]
Without single maturity date	3,832
Amortized Cost	3,832	4,339
Fair Value [Abstract]
Without single maturity date	3,788
Estimated Fair Value	$ 3,788	$ 4,308