LOANS AND ALLOWANCE FOR LOAN LOSSES (Loans Stated at Face Amount, Net of Unearned Income) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Loans stated at face amount, net of unearned income
Loans held for investment, net of deferred fees and costs	$ 5,671,462	$ 5,345,996	$ 3,039,368
Commercial [Member]
Loans stated at face amount, net of unearned income
Loans held for investment, net of deferred fees and costs	4,148,118	3,824,483	2,163,705
Consumer [Member]
Loans stated at face amount, net of unearned income
Loans held for investment, net of deferred fees and costs	1,523,344	1,521,513	$ 875,663
Construction Loans [Member] | Commercial [Member]
Loans stated at face amount, net of unearned income
Loans held for investment, net of deferred fees and costs	484,768	341,280
Construction Loans [Member] | Consumer [Member]
Loans stated at face amount, net of unearned income
Loans held for investment, net of deferred fees and costs	49,359	74,168
Commercial Real Estate - Owner Occupied [Member] | Commercial [Member]
Loans stated at face amount, net of unearned income
Loans held for investment, net of deferred fees and costs	860,086	875,443
Commercial Real Estate - Non-Owner Occupied [Member] | Commercial [Member]
Loans stated at face amount, net of unearned income
Loans held for investment, net of deferred fees and costs	1,618,605	1,509,159
Raw Land and Lots [Member] | Commercial [Member]
Loans stated at face amount, net of unearned income
Loans held for investment, net of deferred fees and costs	195,665	211,225
Single Family Investment Real Estate [Member] | Commercial [Member]
Loans stated at face amount, net of unearned income
Loans held for investment, net of deferred fees and costs	429,489	412,494
Commercial and Industrial [Member] | Commercial [Member]
Loans stated at face amount, net of unearned income
Loans held for investment, net of deferred fees and costs	467,613	393,776
Other Commercial [Member] | Commercial [Member]
Loans stated at face amount, net of unearned income
Loans held for investment, net of deferred fees and costs	91,892	81,106
Mortgage [Member] | Consumer [Member]
Loans stated at face amount, net of unearned income
Loans held for investment, net of deferred fees and costs	474,034	478,151
Indirect Auto [Member] | Consumer [Member]
Loans stated at face amount, net of unearned income
Loans held for investment, net of deferred fees and costs	225,815	199,411
Indirect Marine [Member] | Consumer [Member]
Loans stated at face amount, net of unearned income
Loans held for investment, net of deferred fees and costs	43,717	43,190
HELOCs [Member] | Consumer [Member]
Loans stated at face amount, net of unearned income
Loans held for investment, net of deferred fees and costs	494,192	500,579
Credit Card [Member] | Consumer [Member]
Loans stated at face amount, net of unearned income
Loans held for investment, net of deferred fees and costs		24,225
Other Consumer [Member] | Consumer [Member]
Loans stated at face amount, net of unearned income
Loans held for investment, net of deferred fees and costs	$ 236,227	$ 201,789