LOANS AND ALLOWANCE FOR LOAN LOSSES (Loans Receivables Related Risk Rating Excluding 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
Excluding Purchased Impaired
Financing Receivable, Recorded Investment [Line Items]
Total Loans	7,102,531	6,247,768
Excluding Purchased Impaired | Pass
Financing Receivable, Recorded Investment [Line Items]
Total Loans	6,880,526	6,017,055
Excluding Purchased Impaired | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total Loans	184,654	198,078
Excluding Purchased Impaired | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total Loans	34,114	28,617
Excluding Purchased Impaired | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Total Loans	3,237	4,018
Excluding Purchased Impaired | Construction and Land Development
Financing Receivable, Recorded Investment [Line Items]
Total Loans	945,953	748,209
Excluding Purchased Impaired | Construction and Land Development | Pass
Financing Receivable, Recorded Investment [Line Items]
Total Loans	869,111	667,018
Excluding Purchased Impaired | Construction and Land Development | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total Loans	62,517	69,311
Excluding Purchased Impaired | Construction and Land Development | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total Loans	14,325	11,857
Excluding Purchased Impaired | Construction and Land Development | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Total Loans	0	23
Excluding Purchased Impaired | Commercial Real Estate - Owner Occupied
Financing Receivable, Recorded Investment [Line Items]
Total Loans	929,143	839,462
Excluding Purchased Impaired | Commercial Real Estate - Owner Occupied | Pass
Financing Receivable, Recorded Investment [Line Items]
Total Loans	872,130	801,565
Excluding Purchased Impaired | Commercial Real Estate - Owner Occupied | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total Loans	52,268	32,364
Excluding Purchased Impaired | Commercial Real Estate - Owner Occupied | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total Loans	4,745	5,533
Excluding Purchased Impaired | Commercial Real Estate - Owner Occupied | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Total Loans	0	0
Excluding Purchased Impaired | Commercial Real Estate - Non-Owner Occupied
Financing Receivable, Recorded Investment [Line Items]
Total Loans	1,707,049	1,546,992
Excluding Purchased Impaired | Commercial Real Estate - Non-Owner Occupied | Pass
Financing Receivable, Recorded Investment [Line Items]
Total Loans	1,681,314	1,505,153
Excluding Purchased Impaired | Commercial Real Estate - Non-Owner Occupied | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total Loans	19,899	37,631
Excluding Purchased Impaired | Commercial Real Estate - Non-Owner Occupied | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total Loans	5,836	4,208
Excluding Purchased Impaired | Commercial Real Estate - Non-Owner Occupied | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Total Loans	0	0
Excluding Purchased Impaired | Multifamily Real Estate
Financing Receivable, Recorded Investment [Line Items]
Total Loans	356,999	332,210
Excluding Purchased Impaired | Multifamily Real Estate | Pass
Financing Receivable, Recorded Investment [Line Items]
Total Loans	349,625	312,711
Excluding Purchased Impaired | Multifamily Real Estate | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total Loans	7,374	19,499
Excluding Purchased Impaired | Multifamily Real Estate | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total Loans	0	0
Excluding Purchased Impaired | Multifamily Real Estate | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Total Loans	0	0
Excluding Purchased Impaired | Commercial and Industrial
Financing Receivable, Recorded Investment [Line Items]
Total Loans	611,615	550,452
Excluding Purchased Impaired | Commercial and Industrial | Pass
Financing Receivable, Recorded Investment [Line Items]
Total Loans	595,923	539,999
Excluding Purchased Impaired | Commercial and Industrial | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total Loans	13,533	9,391
Excluding Purchased Impaired | Commercial and Industrial | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total Loans	2,159	1,062
Excluding Purchased Impaired | Commercial and Industrial | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Total Loans	0	0
Excluding Purchased Impaired | Residential 1-4 Family - Commercial
Financing Receivable, Recorded Investment [Line Items]
Total Loans	602,981	539,414
Excluding Purchased Impaired | Residential 1-4 Family - Commercial | Pass
Financing Receivable, Recorded Investment [Line Items]
Total Loans	587,169	523,964
Excluding Purchased Impaired | Residential 1-4 Family - Commercial | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total Loans	12,117	11,715
Excluding Purchased Impaired | Residential 1-4 Family - Commercial | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total Loans	3,650	3,534
Excluding Purchased Impaired | Residential 1-4 Family - Commercial | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Total Loans	45	201
Excluding Purchased Impaired | Residential 1-4 Family - Mortgage
Financing Receivable, Recorded Investment [Line Items]
Total Loans	481,957	473,933
Excluding Purchased Impaired | Residential 1-4 Family - Mortgage | Pass
Financing Receivable, Recorded Investment [Line Items]
Total Loans	470,646	463,009
Excluding Purchased Impaired | Residential 1-4 Family - Mortgage | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total Loans	7,190	6,803
Excluding Purchased Impaired | Residential 1-4 Family - Mortgage | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total Loans	1,642	1,279
Excluding Purchased Impaired | Residential 1-4 Family - Mortgage | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Total Loans	2,479	2,842
Excluding Purchased Impaired | Auto
Financing Receivable, Recorded Investment [Line Items]
Total Loans	282,474	262,071
Excluding Purchased Impaired | Auto | Pass
Financing Receivable, Recorded Investment [Line Items]
Total Loans	278,063	258,188
Excluding Purchased Impaired | Auto | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total Loans	4,131	3,648
Excluding Purchased Impaired | Auto | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total Loans	119	135
Excluding Purchased Impaired | Auto | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Total Loans	161	100
Excluding Purchased Impaired | HELOC
Financing Receivable, Recorded Investment [Line Items]
Total Loans	536,571	525,723
Excluding Purchased Impaired | HELOC | Pass
Financing Receivable, Recorded Investment [Line Items]
Total Loans	531,358	519,928
Excluding Purchased Impaired | HELOC | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total Loans	3,867	4,225
Excluding Purchased Impaired | HELOC | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total Loans	857	969
Excluding Purchased Impaired | HELOC | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Total Loans	489	601
Excluding Purchased Impaired | Consumer and all other
Financing Receivable, Recorded Investment [Line Items]
Total Loans	647,789	429,302
Excluding Purchased Impaired | Consumer and all other | Pass
Financing Receivable, Recorded Investment [Line Items]
Total Loans	645,187	425,520
Excluding Purchased Impaired | Consumer and all other | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total Loans	1,758	3,491
Excluding Purchased Impaired | Consumer and all other | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total Loans	781	40
Excluding Purchased Impaired | Consumer and all other | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Total Loans	$ 63	$ 251