LOANS AND ALLOWANCE FOR LOAN LOSSES (Loans Receivables Related Risk Rating Including Purchased Impaired Loans) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Financing Receivable, Recorded Investment [Line Items]
Total Loans	$ 9,716,207	$ 7,141,552
Construction and Land Development
Financing Receivable, Recorded Investment [Line Items]
Total Loans	1,194,821	948,791
Commercial Real Estate - Owner Occupied
Financing Receivable, Recorded Investment [Line Items]
Total Loans	1,337,345	943,933
Commercial Real Estate - Non-Owner Occupied
Financing Receivable, Recorded Investment [Line Items]
Total Loans	2,467,410	1,713,659
Multifamily Real Estate
Financing Receivable, Recorded Investment [Line Items]
Total Loans	548,231	357,079
Commercial and Industrial
Financing Receivable, Recorded Investment [Line Items]
Total Loans	1,317,135	612,023
Residential 1-4 Family - Commercial
Financing Receivable, Recorded Investment [Line Items]
Total Loans	713,750	612,395
Residential 1-4 Family - Mortgage
Financing Receivable, Recorded Investment [Line Items]
Total Loans	600,578	485,690
Auto
Financing Receivable, Recorded Investment [Line Items]
Total Loans	301,943	282,474
HELOC
Financing Receivable, Recorded Investment [Line Items]
Total Loans	613,383	537,521
Consumer and all other
Financing Receivable, Recorded Investment [Line Items]
Total Loans	621,611	647,987
Purchased Impaired
Financing Receivable, Recorded Investment [Line Items]
Total Loans	90,221	39,021
Purchased Impaired | Construction and Land Development
Financing Receivable, Recorded Investment [Line Items]
Total Loans	8,654	2,838
Purchased Impaired | Commercial Real Estate - Owner Occupied
Financing Receivable, Recorded Investment [Line Items]
Total Loans	25,644	14,790
Purchased Impaired | Commercial Real Estate - Non-Owner Occupied
Financing Receivable, Recorded Investment [Line Items]
Total Loans	17,335	6,610
Purchased Impaired | Multifamily Real Estate
Financing Receivable, Recorded Investment [Line Items]
Total Loans	88	80
Purchased Impaired | Commercial and Industrial
Financing Receivable, Recorded Investment [Line Items]
Total Loans	2,156	408
Purchased Impaired | Residential 1-4 Family - Commercial
Financing Receivable, Recorded Investment [Line Items]
Total Loans	13,707	9,414
Purchased Impaired | Residential 1-4 Family - Mortgage
Financing Receivable, Recorded Investment [Line Items]
Total Loans	16,766	3,733
Purchased Impaired | Auto
Financing Receivable, Recorded Investment [Line Items]
Total Loans	7	0
Purchased Impaired | HELOC
Financing Receivable, Recorded Investment [Line Items]
Total Loans	5,115	950
Purchased Impaired | Consumer and all other
Financing Receivable, Recorded Investment [Line Items]
Total Loans	749	198
Purchased Impaired | Pass
Financing Receivable, Recorded Investment [Line Items]
Total Loans	35,658	19,017
Purchased Impaired | Pass | Construction and Land Development
Financing Receivable, Recorded Investment [Line Items]
Total Loans	1,835	1,462
Purchased Impaired | Pass | Commercial Real Estate - Owner Occupied
Financing Receivable, Recorded Investment [Line Items]
Total Loans	8,347	4,958
Purchased Impaired | Pass | Commercial Real Estate - Non-Owner Occupied
Financing Receivable, Recorded Investment [Line Items]
Total Loans	4,789	3,920
Purchased Impaired | Pass | Multifamily Real Estate
Financing Receivable, Recorded Investment [Line Items]
Total Loans	0	0
Purchased Impaired | Pass | Commercial and Industrial
Financing Receivable, Recorded Investment [Line Items]
Total Loans	762	85
Purchased Impaired | Pass | Residential 1-4 Family - Commercial
Financing Receivable, Recorded Investment [Line Items]
Total Loans	6,512	5,234
Purchased Impaired | Pass | Residential 1-4 Family - Mortgage
Financing Receivable, Recorded Investment [Line Items]
Total Loans	9,894	2,764
Purchased Impaired | Pass | Auto
Financing Receivable, Recorded Investment [Line Items]
Total Loans	7
Purchased Impaired | Pass | HELOC
Financing Receivable, Recorded Investment [Line Items]
Total Loans	3,438	446
Purchased Impaired | Pass | Consumer and all other
Financing Receivable, Recorded Investment [Line Items]
Total Loans	74	148
Purchased Impaired | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total Loans	21,699	13,881
Purchased Impaired | Special Mention | Construction and Land Development
Financing Receivable, Recorded Investment [Line Items]
Total Loans	1,308	1,260
Purchased Impaired | Special Mention | Commercial Real Estate - Owner Occupied
Financing Receivable, Recorded Investment [Line Items]
Total Loans	6,685	7,486
Purchased Impaired | Special Mention | Commercial Real Estate - Non-Owner Occupied
Financing Receivable, Recorded Investment [Line Items]
Total Loans	7,992	1,394
Purchased Impaired | Special Mention | Multifamily Real Estate
Financing Receivable, Recorded Investment [Line Items]
Total Loans	88	80
Purchased Impaired | Special Mention | Commercial and Industrial
Financing Receivable, Recorded Investment [Line Items]
Total Loans	134	123
Purchased Impaired | Special Mention | Residential 1-4 Family - Commercial
Financing Receivable, Recorded Investment [Line Items]
Total Loans	2,771	2,877
Purchased Impaired | Special Mention | Residential 1-4 Family - Mortgage
Financing Receivable, Recorded Investment [Line Items]
Total Loans	1,030	329
Purchased Impaired | Special Mention | Auto
Financing Receivable, Recorded Investment [Line Items]
Total Loans	0
Purchased Impaired | Special Mention | HELOC
Financing Receivable, Recorded Investment [Line Items]
Total Loans	1,031	291
Purchased Impaired | Special Mention | Consumer and all other
Financing Receivable, Recorded Investment [Line Items]
Total Loans	660	41
Purchased Impaired | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total Loans	32,864	5,435
Purchased Impaired | Substandard | Construction and Land Development
Financing Receivable, Recorded Investment [Line Items]
Total Loans	5,511	116
Purchased Impaired | Substandard | Commercial Real Estate - Owner Occupied
Financing Receivable, Recorded Investment [Line Items]
Total Loans	10,612	2,346
Purchased Impaired | Substandard | Commercial Real Estate - Non-Owner Occupied
Financing Receivable, Recorded Investment [Line Items]
Total Loans	4,554	1,296
Purchased Impaired | Substandard | Multifamily Real Estate
Financing Receivable, Recorded Investment [Line Items]
Total Loans	0	0
Purchased Impaired | Substandard | Commercial and Industrial
Financing Receivable, Recorded Investment [Line Items]
Total Loans	1,260	200
Purchased Impaired | Substandard | Residential 1-4 Family - Commercial
Financing Receivable, Recorded Investment [Line Items]
Total Loans	4,424	1,303
Purchased Impaired | Substandard | Residential 1-4 Family - Mortgage
Financing Receivable, Recorded Investment [Line Items]
Total Loans	5,842	71
Purchased Impaired | Substandard | Auto
Financing Receivable, Recorded Investment [Line Items]
Total Loans	0
Purchased Impaired | Substandard | HELOC
Financing Receivable, Recorded Investment [Line Items]
Total Loans	646	94
Purchased Impaired | Substandard | Consumer and all other
Financing Receivable, Recorded Investment [Line Items]
Total Loans	15	9
Purchased Impaired | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Total Loans	0	688
Purchased Impaired | Doubtful | Construction and Land Development
Financing Receivable, Recorded Investment [Line Items]
Total Loans	0	0
Purchased Impaired | Doubtful | Commercial Real Estate - Owner Occupied
Financing Receivable, Recorded Investment [Line Items]
Total Loans	0	0
Purchased Impaired | Doubtful | Commercial Real Estate - Non-Owner Occupied
Financing Receivable, Recorded Investment [Line Items]
Total Loans	0	0
Purchased Impaired | Doubtful | Multifamily Real Estate
Financing Receivable, Recorded Investment [Line Items]
Total Loans	0	0
Purchased Impaired | Doubtful | Commercial and Industrial
Financing Receivable, Recorded Investment [Line Items]
Total Loans	0	0
Purchased Impaired | Doubtful | Residential 1-4 Family - Commercial
Financing Receivable, Recorded Investment [Line Items]
Total Loans	0	0
Purchased Impaired | Doubtful | Residential 1-4 Family - Mortgage
Financing Receivable, Recorded Investment [Line Items]
Total Loans	0	569
Purchased Impaired | Doubtful | Auto
Financing Receivable, Recorded Investment [Line Items]
Total Loans	0
Purchased Impaired | Doubtful | HELOC
Financing Receivable, Recorded Investment [Line Items]
Total Loans	0	119
Purchased Impaired | Doubtful | Consumer and all other
Financing Receivable, Recorded Investment [Line Items]
Total Loans	$ 0	$ 0