LOANS AND ALLOWANCE FOR LOAN LOSSES (Summary of Aging of the Loan Portfolio by Class) (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Jan. 01, 2020	Dec. 31, 2019
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	$ 14,228,554		$ 12,419,378
Greater Than 90 Days and Still Accruing	19,255		13,396
Nonaccrual	39,624	$ 45,204	28,232
Total Loans	14,308,646		12,610,936
30-59 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	12,003		50,453
60-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	9,210		12,796
Purchased Impaired
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current			70,267
Total Loans	73,200		86,681
Purchased Impaired | 30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due			3,221
Purchased Impaired | 90+ Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due			13,193
Construction and Land Development
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	1,241,512		1,231,043
Greater Than 90 Days and Still Accruing	473		189
Nonaccrual	3,977	4,060	3,703
Total Loans	1,247,939		1,250,924
Construction and Land Development | 30-59 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	1,683		4,563
Construction and Land Development | 60-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	294		482
Construction and Land Development | Purchased Impaired
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current			10,465
Total Loans			10,944
Construction and Land Development | Purchased Impaired | 30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due			136
Construction and Land Development | Purchased Impaired | 90+ Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due			343
Commercial Real Estate - Owner Occupied
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	2,048,203		2,001,074
Greater Than 90 Days and Still Accruing	7,851		1,062
Nonaccrual	8,924	13,889	6,003
Total Loans	2,067,087		2,041,243
Commercial Real Estate - Owner Occupied | 30-59 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	1,679		3,482
Commercial Real Estate - Owner Occupied | 60-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	430		2,184
Commercial Real Estate - Owner Occupied | Purchased Impaired
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current			20,074
Total Loans			27,438
Commercial Real Estate - Owner Occupied | Purchased Impaired | 30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due			480
Commercial Real Estate - Owner Occupied | Purchased Impaired | 90+ Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due			6,884
Commercial Real Estate - Non-Owner Occupied
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	3,451,071		3,269,244
Greater Than 90 Days and Still Accruing	878		1,451
Nonaccrual	1,877	1,368	381
Total Loans	3,455,125		3,286,098
Commercial Real Estate - Non-Owner Occupied | 30-59 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	930		457
Commercial Real Estate - Non-Owner Occupied | 60-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	369		0
Commercial Real Estate - Non-Owner Occupied | Purchased Impaired
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current			12,730
Total Loans			14,565
Commercial Real Estate - Non-Owner Occupied | Purchased Impaired | 30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due			848
Commercial Real Estate - Non-Owner Occupied | Purchased Impaired | 90+ Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due			987
Multifamily Real Estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	717,320		632,952
Greater Than 90 Days and Still Accruing	366		474
Nonaccrual	33	0	0
Total Loans	717,719		633,743
Multifamily Real Estate | 30-59 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due			223
Multifamily Real Estate | 60-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due			0
Multifamily Real Estate | Purchased Impaired
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current			94
Total Loans			94
Multifamily Real Estate | Purchased Impaired | 30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due			0
Multifamily Real Estate | Purchased Impaired | 90+ Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due			0
Commercial and Industrial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	3,551,187		2,099,974
Greater Than 90 Days and Still Accruing	178		449
Nonaccrual	2,708	3,037	1,735
Total Loans	3,555,971		2,114,033
Commercial and Industrial | 30-59 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	1,602		8,698
Commercial and Industrial | 60-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	296		1,598
Commercial and Industrial | Purchased Impaired
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current			590
Total Loans			1,579
Commercial and Industrial | Purchased Impaired | 90+ Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due			989
Residential 1-4 Family - Commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	706,437		703,471
Greater Than 90 Days and Still Accruing	578		674
Nonaccrual	5,784	6,492	4,301
Total Loans	715,384		724,337
Residential 1-4 Family - Commercial | 30-59 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	480		1,479
Residential 1-4 Family - Commercial | 60-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	2,105		2,207
Residential 1-4 Family - Commercial | Purchased Impaired
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current			9,667
Total Loans			12,205
Residential 1-4 Family - Commercial | Purchased Impaired | 30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due			543
Residential 1-4 Family - Commercial | Purchased Impaired | 90+ Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due			1,995
Residential 1-4 Family - Consumer
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	818,877		842,667
Greater Than 90 Days and Still Accruing	5,099		4,515
Nonaccrual	12,029	13,117	9,292
Total Loans	841,051		890,503
Residential 1-4 Family - Consumer | 30-59 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	1,229		16,244
Total Loans	1,229
Residential 1-4 Family - Consumer | 60-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	3,817		3,072
Total Loans	3,817
Residential 1-4 Family - Consumer | 90+ Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans	5,099
Residential 1-4 Family - Consumer | Purchased Impaired
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current			12,005
Total Loans			14,713
Residential 1-4 Family - Consumer | Purchased Impaired | 30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due			927
Residential 1-4 Family - Consumer | Purchased Impaired | 90+ Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due			1,781
Residential 1-4 Family - Revolving
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	619,172		637,966
Greater Than 90 Days and Still Accruing	1,995		3,357
Nonaccrual	3,626	2,490	2,080
Total Loans	627,765		659,504
Residential 1-4 Family - Revolving | 30-59 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	1,924		10,190
Total Loans	1,924
Residential 1-4 Family - Revolving | 60-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	1,048		1,784
Total Loans	1,048
Residential 1-4 Family - Revolving | 90+ Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans	1,995
Residential 1-4 Family - Revolving | Purchased Impaired
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current			3,635
Total Loans			4,127
Residential 1-4 Family - Revolving | Purchased Impaired | 30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due			287
Residential 1-4 Family - Revolving | Purchased Impaired | 90+ Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due			205
Auto
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	377,822		346,819
Greater Than 90 Days and Still Accruing	181		272
Nonaccrual	584	565	563
Total Loans	380,053		350,419
Auto | 30-59 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	1,176		2,525
Total Loans	1,176
Auto | 60-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	290		236
Total Loans	290
Auto | 90+ Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans	181
Auto | Purchased Impaired
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current			4
Total Loans			4
Consumer
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	308,719		367,794
Greater Than 90 Days and Still Accruing	1,157		953
Nonaccrual	81	88	77
Total Loans	311,362		372,853
Consumer | 30-59 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	844		2,128
Total Loans	844
Consumer | 60-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	561		1,233
Total Loans	561
Consumer | 90+ Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans	1,157
Consumer | Purchased Impaired
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current			659
Total Loans			668
Consumer | Purchased Impaired | 90+ Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due			9
Other Commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	388,234		286,374
Greater Than 90 Days and Still Accruing	499		0
Nonaccrual	1	$ 98	97
Total Loans	389,190		287,279
Other Commercial | 30-59 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	$ 456		464
Other Commercial | 60-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due			0
Other Commercial | Purchased Impaired
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current			344
Total Loans			344
Other Commercial | Purchased Impaired | 30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due			0
Other Commercial | Purchased Impaired | 90+ Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due			$ 0