LOANS AND ALLOWANCE FOR LOAN LOSSES (Loans Receivables Related Risk Rating Including Purchased Impaired Loans) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Financing Receivable, Recorded Investment [Line Items]
Total Loans	$ 7,141,552	$ 6,307,060	$ 5,671,462
Construction and Land Development
Financing Receivable, Recorded Investment [Line Items]
Total Loans	948,791	751,131	749,720
Commercial Real Estate - Owner Occupied
Financing Receivable, Recorded Investment [Line Items]
Total Loans	943,933	857,805	860,086
Commercial Real Estate - Non-Owner Occupied
Financing Receivable, Recorded Investment [Line Items]
Total Loans	1,713,659	1,564,295	1,270,480
Multifamily Real Estate
Financing Receivable, Recorded Investment [Line Items]
Total Loans	357,079	334,276	322,528
Commercial and Industrial
Financing Receivable, Recorded Investment [Line Items]
Total Loans	612,023	551,526	435,365
Residential 1-4 Family - Commercial
Financing Receivable, Recorded Investment [Line Items]
Total Loans	612,395	551,636	517,063
Residential 1-4 Family - Mortgage
Financing Receivable, Recorded Investment [Line Items]
Total Loans	485,690	477,911	461,406
Auto
Financing Receivable, Recorded Investment [Line Items]
Total Loans	282,474	262,071	234,061
HELOC
Financing Receivable, Recorded Investment [Line Items]
Total Loans	537,521	526,884	516,726
Consumer and all other
Financing Receivable, Recorded Investment [Line Items]
Total Loans	647,987	429,525	304,027
Purchased Impaired
Financing Receivable, Recorded Investment [Line Items]
Total Loans	39,021	59,292	73,737
Purchased Impaired | Construction and Land Development
Financing Receivable, Recorded Investment [Line Items]
Total Loans	2,838	2,922	5,986
Purchased Impaired | Commercial Real Estate - Owner Occupied
Financing Receivable, Recorded Investment [Line Items]
Total Loans	14,790	18,343	27,388
Purchased Impaired | Commercial Real Estate - Non-Owner Occupied
Financing Receivable, Recorded Investment [Line Items]
Total Loans	6,610	17,303	13,519
Purchased Impaired | Multifamily Real Estate
Financing Receivable, Recorded Investment [Line Items]
Total Loans	80	2,066	1,555
Purchased Impaired | Commercial and Industrial
Financing Receivable, Recorded Investment [Line Items]
Total Loans	408	1,074	1,813
Purchased Impaired | Residential 1-4 Family - Commercial
Financing Receivable, Recorded Investment [Line Items]
Total Loans	9,414	12,222	16,119
Purchased Impaired | Residential 1-4 Family - Mortgage
Financing Receivable, Recorded Investment [Line Items]
Total Loans	3,733	3,978	5,040
Purchased Impaired | Auto
Financing Receivable, Recorded Investment [Line Items]
Total Loans	0	0	0
Purchased Impaired | HELOC
Financing Receivable, Recorded Investment [Line Items]
Total Loans	950	1,161	1,791
Purchased Impaired | Consumer and all other
Financing Receivable, Recorded Investment [Line Items]
Total Loans	198	223	$ 526
Purchased Impaired | Pass
Financing Receivable, Recorded Investment [Line Items]
Total Loans	19,017	27,569
Purchased Impaired | Pass | Construction and Land Development
Financing Receivable, Recorded Investment [Line Items]
Total Loans	1,462	1,092
Purchased Impaired | Pass | Commercial Real Estate - Owner Occupied
Financing Receivable, Recorded Investment [Line Items]
Total Loans	4,958	5,520
Purchased Impaired | Pass | Commercial Real Estate - Non-Owner Occupied
Financing Receivable, Recorded Investment [Line Items]
Total Loans	3,920	10,927
Purchased Impaired | Pass | Multifamily Real Estate
Financing Receivable, Recorded Investment [Line Items]
Total Loans	0	343
Purchased Impaired | Pass | Commercial and Industrial
Financing Receivable, Recorded Investment [Line Items]
Total Loans	85	107
Purchased Impaired | Pass | Residential 1-4 Family - Commercial
Financing Receivable, Recorded Investment [Line Items]
Total Loans	5,234	5,959
Purchased Impaired | Pass | Residential 1-4 Family - Mortgage
Financing Receivable, Recorded Investment [Line Items]
Total Loans	2,764	2,598
Purchased Impaired | Pass | HELOC
Financing Receivable, Recorded Investment [Line Items]
Total Loans	446	857
Purchased Impaired | Pass | Consumer and all other
Financing Receivable, Recorded Investment [Line Items]
Total Loans	148	166
Purchased Impaired | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total Loans	13,881	21,837
Purchased Impaired | Special Mention | Construction and Land Development
Financing Receivable, Recorded Investment [Line Items]
Total Loans	1,260	1,432
Purchased Impaired | Special Mention | Commercial Real Estate - Owner Occupied
Financing Receivable, Recorded Investment [Line Items]
Total Loans	7,486	8,889
Purchased Impaired | Special Mention | Commercial Real Estate - Non-Owner Occupied
Financing Receivable, Recorded Investment [Line Items]
Total Loans	1,394	4,638
Purchased Impaired | Special Mention | Multifamily Real Estate
Financing Receivable, Recorded Investment [Line Items]
Total Loans	80	1,723
Purchased Impaired | Special Mention | Commercial and Industrial
Financing Receivable, Recorded Investment [Line Items]
Total Loans	123	480
Purchased Impaired | Special Mention | Residential 1-4 Family - Commercial
Financing Receivable, Recorded Investment [Line Items]
Total Loans	2,877	3,943
Purchased Impaired | Special Mention | Residential 1-4 Family - Mortgage
Financing Receivable, Recorded Investment [Line Items]
Total Loans	329	512
Purchased Impaired | Special Mention | HELOC
Financing Receivable, Recorded Investment [Line Items]
Total Loans	291	183
Purchased Impaired | Special Mention | Consumer and all other
Financing Receivable, Recorded Investment [Line Items]
Total Loans	41	37
Purchased Impaired | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total Loans	5,435	9,256
Purchased Impaired | Substandard | Construction and Land Development
Financing Receivable, Recorded Investment [Line Items]
Total Loans	116	398
Purchased Impaired | Substandard | Commercial Real Estate - Owner Occupied
Financing Receivable, Recorded Investment [Line Items]
Total Loans	2,346	3,934
Purchased Impaired | Substandard | Commercial Real Estate - Non-Owner Occupied
Financing Receivable, Recorded Investment [Line Items]
Total Loans	1,296	1,738
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	200	487
Purchased Impaired | Substandard | Residential 1-4 Family - Commercial
Financing Receivable, Recorded Investment [Line Items]
Total Loans	1,303	2,320
Purchased Impaired | Substandard | Residential 1-4 Family - Mortgage
Financing Receivable, Recorded Investment [Line Items]
Total Loans	71	352
Purchased Impaired | Substandard | HELOC
Financing Receivable, Recorded Investment [Line Items]
Total Loans	94	7
Purchased Impaired | Substandard | Consumer and all other
Financing Receivable, Recorded Investment [Line Items]
Total Loans	9	20
Purchased Impaired | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Total Loans	688	630
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	569	516
Purchased Impaired | Doubtful | HELOC
Financing Receivable, Recorded Investment [Line Items]
Total Loans	119	114
Purchased Impaired | Doubtful | Consumer and all other
Financing Receivable, Recorded Investment [Line Items]
Total Loans	$ 0	$ 0