LOANS - Credit Risk Profile of Loans (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017	Jun. 30, 2017
Financing Receivable, Recorded Investment [Line Items]
Purchased Credit Impaired	$ 10,717	$ 15,965
Total loans held for investment	3,222,108	3,190,485	$ 3,123,355
Grade 1 - 4 (Pass)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	2,801,654	2,767,798
Grade 5 (Watch)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	194,803	146,999
Grade 6 (Special Mention)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	88,942	130,126
Grade 7 (Substandard-Accrual)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	71,163	72,259
Grade 8 (Substandard-Nonaccrual)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	54,829	57,338
Grade 9 (Doubtful)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	0	0
Commercial & industrial
Financing Receivable, Recorded Investment [Line Items]
Total loans held for investment	1,070,420	1,066,266
Mortgage warehouse
Financing Receivable, Recorded Investment [Line Items]
Total loans held for investment	244,041	220,230
Owner occupied commercial real estate
Financing Receivable, Recorded Investment [Line Items]
Total loans held for investment	436,153	415,230
Commercial real estate
Financing Receivable, Recorded Investment [Line Items]
Total loans held for investment	1,092,036	1,067,779
Construction, land & land development
Financing Receivable, Recorded Investment [Line Items]
Total loans held for investment	130,533	164,952
Residential mortgage
Financing Receivable, Recorded Investment [Line Items]
Total loans held for investment	235,192	238,580
Consumer and other
Financing Receivable, Recorded Investment [Line Items]
Total loans held for investment	13,733	17,448
Originated
Financing Receivable, Recorded Investment [Line Items]
Purchased Credit Impaired	0	0
Total loans held for investment	2,878,964	2,676,491	2,476,754
Originated | Grade 1 - 4 (Pass)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	2,542,691	2,382,372
Originated | Grade 5 (Watch)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	164,508	78,394
Originated | Grade 6 (Special Mention)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	51,970	98,694
Originated | Grade 7 (Substandard-Accrual)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	69,351	65,171
Originated | Grade 8 (Substandard-Nonaccrual)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	50,444	51,860
Originated | Grade 9 (Doubtful)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	0	0
Originated | Commercial & industrial
Financing Receivable, Recorded Investment [Line Items]
Purchased Credit Impaired	0	0
Total loans held for investment	1,034,821	1,002,797
Originated | Commercial & industrial | Grade 1 - 4 (Pass)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	895,299	889,709
Originated | Commercial & industrial | Grade 5 (Watch)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	65,009	22,648
Originated | Commercial & industrial | Grade 6 (Special Mention)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	22,153	5,605
Originated | Commercial & industrial | Grade 7 (Substandard-Accrual)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	11,327	39,422
Originated | Commercial & industrial | Grade 8 (Substandard-Nonaccrual)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	41,033	45,413
Originated | Commercial & industrial | Grade 9 (Doubtful)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	0	0
Originated | Mortgage warehouse
Financing Receivable, Recorded Investment [Line Items]
Purchased Credit Impaired	0	0
Total loans held for investment	244,041	220,230
Originated | Mortgage warehouse | Grade 1 - 4 (Pass)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	244,041	220,230
Originated | Mortgage warehouse | Grade 5 (Watch)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	0	0
Originated | Mortgage warehouse | Grade 6 (Special Mention)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	0	0
Originated | Mortgage warehouse | Grade 7 (Substandard-Accrual)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	0	0
Originated | Mortgage warehouse | Grade 8 (Substandard-Nonaccrual)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	0	0
Originated | Mortgage warehouse | Grade 9 (Doubtful)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	0	0
Originated | Owner occupied commercial real estate
Financing Receivable, Recorded Investment [Line Items]
Purchased Credit Impaired	0	0
Total loans held for investment	373,692	327,906	306,514
Originated | Owner occupied commercial real estate | Grade 1 - 4 (Pass)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	342,441	314,497
Originated | Owner occupied commercial real estate | Grade 5 (Watch)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	18,036	3,096
Originated | Owner occupied commercial real estate | Grade 6 (Special Mention)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	4,649	7,658
Originated | Owner occupied commercial real estate | Grade 7 (Substandard-Accrual)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	3,341	2,655
Originated | Owner occupied commercial real estate | Grade 8 (Substandard-Nonaccrual)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	5,225	0
Originated | Owner occupied commercial real estate | Grade 9 (Doubtful)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	0	0
Originated | Commercial real estate
Financing Receivable, Recorded Investment [Line Items]
Purchased Credit Impaired	0	0
Total loans held for investment	949,099	823,361	807,341
Originated | Commercial real estate | Grade 1 - 4 (Pass)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	799,637	681,691
Originated | Commercial real estate | Grade 5 (Watch)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	77,763	45,149
Originated | Commercial real estate | Grade 6 (Special Mention)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	23,652	85,431
Originated | Commercial real estate | Grade 7 (Substandard-Accrual)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	47,872	11,090
Originated | Commercial real estate | Grade 8 (Substandard-Nonaccrual)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	175	0
Originated | Commercial real estate | Grade 9 (Doubtful)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	0	0
Originated | Construction, land & land development
Financing Receivable, Recorded Investment [Line Items]
Purchased Credit Impaired	0	0
Total loans held for investment	105,926	136,998	153,522
Originated | Construction, land & land development | Grade 1 - 4 (Pass)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	94,902	121,893
Originated | Construction, land & land development | Grade 5 (Watch)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	3,686	970
Originated | Construction, land & land development | Grade 6 (Special Mention)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	1,457	0
Originated | Construction, land & land development | Grade 7 (Substandard-Accrual)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	5,774	10,848
Originated | Construction, land & land development | Grade 8 (Substandard-Nonaccrual)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	107	3,287
Originated | Construction, land & land development | Grade 9 (Doubtful)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	0	0
Originated | Residential mortgage
Financing Receivable, Recorded Investment [Line Items]
Purchased Credit Impaired	0	0
Total loans held for investment	158,531	149,021	137,918
Originated | Residential mortgage | Grade 1 - 4 (Pass)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	153,588	138,239
Originated | Residential mortgage | Grade 5 (Watch)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	14	6,529
Originated | Residential mortgage | Grade 6 (Special Mention)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	59	0
Originated | Residential mortgage | Grade 7 (Substandard-Accrual)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	1,011	1,142
Originated | Residential mortgage | Grade 8 (Substandard-Nonaccrual)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	3,859	3,111
Originated | Residential mortgage | Grade 9 (Doubtful)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	0	0
Originated | Consumer and other
Financing Receivable, Recorded Investment [Line Items]
Purchased Credit Impaired	0	0
Total loans held for investment	12,854	16,178	19,105
Originated | Consumer and other | Grade 1 - 4 (Pass)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	12,783	16,113
Originated | Consumer and other | Grade 5 (Watch)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	0	2
Originated | Consumer and other | Grade 6 (Special Mention)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	0	0
Originated | Consumer and other | Grade 7 (Substandard-Accrual)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	26	14
Originated | Consumer and other | Grade 8 (Substandard-Nonaccrual)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	45	49
Originated | Consumer and other | Grade 9 (Doubtful)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	0	0
Acquired
Financing Receivable, Recorded Investment [Line Items]
Purchased Credit Impaired	10,717	15,965
Total loans held for investment	343,144	513,994	646,601
Acquired | Grade 1 - 4 (Pass)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	258,963	385,426
Acquired | Grade 5 (Watch)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	30,295	68,605
Acquired | Grade 6 (Special Mention)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	36,972	31,432
Acquired | Grade 7 (Substandard-Accrual)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	1,812	7,088
Acquired | Grade 8 (Substandard-Nonaccrual)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	4,385	5,478
Acquired | Grade 9 (Doubtful)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	0	0
Acquired | Commercial & industrial
Financing Receivable, Recorded Investment [Line Items]
Purchased Credit Impaired	1,730	3,237
Total loans held for investment	35,599	63,469	91,978
Acquired | Commercial & industrial | Grade 1 - 4 (Pass)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	17,645	38,000
Acquired | Commercial & industrial | Grade 5 (Watch)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	6,596	3,172
Acquired | Commercial & industrial | Grade 6 (Special Mention)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	7,750	11,101
Acquired | Commercial & industrial | Grade 7 (Substandard-Accrual)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	132	6,058
Acquired | Commercial & industrial | Grade 8 (Substandard-Nonaccrual)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	1,746	1,901
Acquired | Commercial & industrial | Grade 9 (Doubtful)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	0	0
Acquired | Mortgage warehouse
Financing Receivable, Recorded Investment [Line Items]
Total loans held for investment	0	0
Acquired | Owner occupied commercial real estate
Financing Receivable, Recorded Investment [Line Items]
Purchased Credit Impaired	3,394	4,062
Total loans held for investment	62,461	87,324	100,803
Acquired | Owner occupied commercial real estate | Grade 1 - 4 (Pass)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	47,744	72,592
Acquired | Owner occupied commercial real estate | Grade 5 (Watch)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	7,314	8,499
Acquired | Owner occupied commercial real estate | Grade 6 (Special Mention)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	2,003	0
Acquired | Owner occupied commercial real estate | Grade 7 (Substandard-Accrual)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	279	285
Acquired | Owner occupied commercial real estate | Grade 8 (Substandard-Nonaccrual)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	1,727	1,886
Acquired | Owner occupied commercial real estate | Grade 9 (Doubtful)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	0	0
Acquired | Commercial real estate
Financing Receivable, Recorded Investment [Line Items]
Purchased Credit Impaired	3,591	6,437
Total loans held for investment	142,937	244,418	301,896
Acquired | Commercial real estate | Grade 1 - 4 (Pass)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	107,919	173,765
Acquired | Commercial real estate | Grade 5 (Watch)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	4,232	43,775
Acquired | Commercial real estate | Grade 6 (Special Mention)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	26,822	20,129
Acquired | Commercial real estate | Grade 7 (Substandard-Accrual)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	268	0
Acquired | Commercial real estate | Grade 8 (Substandard-Nonaccrual)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	105	312
Acquired | Commercial real estate | Grade 9 (Doubtful)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	0	0
Acquired | Construction, land & land development
Financing Receivable, Recorded Investment [Line Items]
Purchased Credit Impaired	0	0
Total loans held for investment	24,607	27,954	48,470
Acquired | Construction, land & land development | Grade 1 - 4 (Pass)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	11,401	14,549
Acquired | Construction, land & land development | Grade 5 (Watch)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	11,951	12,136
Acquired | Construction, land & land development | Grade 6 (Special Mention)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	0	0
Acquired | Construction, land & land development | Grade 7 (Substandard-Accrual)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	555	555
Acquired | Construction, land & land development | Grade 8 (Substandard-Nonaccrual)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	700	714
Acquired | Construction, land & land development | Grade 9 (Doubtful)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	0	0
Acquired | Residential mortgage
Financing Receivable, Recorded Investment [Line Items]
Purchased Credit Impaired	2,002	2,229
Total loans held for investment	76,661	89,559	101,916
Acquired | Residential mortgage | Grade 1 - 4 (Pass)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	73,597	85,461
Acquired | Residential mortgage | Grade 5 (Watch)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	202	1,023
Acquired | Residential mortgage | Grade 6 (Special Mention)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	197	202
Acquired | Residential mortgage | Grade 7 (Substandard-Accrual)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	559	190
Acquired | Residential mortgage | Grade 8 (Substandard-Nonaccrual)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	104	454
Acquired | Residential mortgage | Grade 9 (Doubtful)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	0	0
Acquired | Consumer and other
Financing Receivable, Recorded Investment [Line Items]
Purchased Credit Impaired	0	0
Total loans held for investment	879	1,270	$ 1,538
Acquired | Consumer and other | Grade 1 - 4 (Pass)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	657	1,059
Acquired | Consumer and other | Grade 5 (Watch)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	0	0
Acquired | Consumer and other | Grade 6 (Special Mention)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	200	0
Acquired | Consumer and other | Grade 7 (Substandard-Accrual)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	19	0
Acquired | Consumer and other | Grade 8 (Substandard-Nonaccrual)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	3	211
Acquired | Consumer and other | Grade 9 (Doubtful)
Financing Receivable, Recorded Investment [Line Items]
Loans, credit risk profile	$ 0	$ 0