LOANS AND ALLOWANCE FOR LOAN LOSSES (Loans Stated at Face Amount, Net of Deferred Fees and Costs) (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015	Sep. 30, 2015
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans held for investment, net	$ 6,148,918	$ 5,671,462	$ 5,543,621
Loans receivable, deferred fees and costs	3,300	3,000
Construction and Land Development
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans held for investment, net	776,430	749,720	694,645
Commercial Real Estate - Owner Occupied
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans held for investment, net	857,142	860,086	863,578
Commercial Real Estate - Non-Owner Occupied
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans held for investment, net	1,454,828	1,270,480	1,223,607
Multifamily Real Estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans held for investment, net	339,313	322,528	329,959
Commercial & Industrial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans held for investment, net	509,857	435,365	409,657
Residential 1-4 Family
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans held for investment, net	999,361	978,469	987,788
Auto
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans held for investment, net	255,188	234,061	225,994
HELOC
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans held for investment, net	524,097	516,726	514,362
Consumer and all other
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans held for investment, net	$ 432,702	$ 304,027	$ 294,031