LOANS AND ALLOWANCE FOR LOAN LOSSES (Loans Receivables Related Risk Rating Excluding Purchased Impaired Loans) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	$ 5,387,755	$ 5,345,996	$ 5,274,198
Commercial Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	358,436	341,280
Commercial Real Estate - Owner Occupied [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	898,222	875,443
Commercial Real Estate - Non-Owner Occupied [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	1,518,590	1,509,159
Raw Land and Lots [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	197,759	211,225
Single Family Investment Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	416,984	412,494
Commercial and Industrial [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	426,490	393,776
Other Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	80,416	81,106
Excluding Purchased Impaired [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	3,815,742	3,730,248
Excluding Purchased Impaired [Member] | Commercial Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	355,346	337,498
Excluding Purchased Impaired [Member] | Commercial Real Estate - Owner Occupied [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	867,218	844,276
Excluding Purchased Impaired [Member] | Commercial Real Estate - Non-Owner Occupied [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	1,499,015	1,480,290
Excluding Purchased Impaired [Member] | Raw Land and Lots [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	191,704	203,798
Excluding Purchased Impaired [Member] | Single Family Investment Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	400,685	395,615
Excluding Purchased Impaired [Member] | Commercial and Industrial [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	423,152	389,921
Excluding Purchased Impaired [Member] | Other Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	78,622	78,850
Excluding Purchased Impaired [Member] | 1-3 [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	854,880	805,908
Excluding Purchased Impaired [Member] | 1-3 [Member] | Commercial Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	32,325	22,512
Excluding Purchased Impaired [Member] | 1-3 [Member] | Commercial Real Estate - Owner Occupied [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	185,029	185,789
Excluding Purchased Impaired [Member] | 1-3 [Member] | Commercial Real Estate - Non-Owner Occupied [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	368,352	356,263
Excluding Purchased Impaired [Member] | 1-3 [Member] | Raw Land and Lots [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	9,550	11,162
Excluding Purchased Impaired [Member] | 1-3 [Member] | Single Family Investment Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	62,254	59,638
Excluding Purchased Impaired [Member] | 1-3 [Member] | Commercial and Industrial [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	165,924	138,973
Excluding Purchased Impaired [Member] | 1-3 [Member] | Other Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	31,446	31,571
Excluding Purchased Impaired [Member] | 4 [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	2,719,393	2,662,344
Excluding Purchased Impaired [Member] | 4 [Member] | Commercial Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	295,831	289,064
Excluding Purchased Impaired [Member] | 4 [Member] | Commercial Real Estate - Owner Occupied [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	644,950	620,587
Excluding Purchased Impaired [Member] | 4 [Member] | Commercial Real Estate - Non-Owner Occupied [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	1,059,097	1,041,515
Excluding Purchased Impaired [Member] | 4 [Member] | Raw Land and Lots [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	126,001	128,281
Excluding Purchased Impaired [Member] | 4 [Member] | Single Family Investment Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	316,576	311,900
Excluding Purchased Impaired [Member] | 4 [Member] | Commercial and Industrial [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	236,174	230,084
Excluding Purchased Impaired [Member] | 4 [Member] | Other Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	40,764	40,913
Excluding Purchased Impaired [Member] | 5 [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	80,919	89,056
Excluding Purchased Impaired [Member] | 5 [Member] | Commercial Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	12,537	11,932
Excluding Purchased Impaired [Member] | 5 [Member] | Commercial Real Estate - Owner Occupied [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	12,608	15,003
Excluding Purchased Impaired [Member] | 5 [Member] | Commercial Real Estate - Non-Owner Occupied [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	21,457	22,358
Excluding Purchased Impaired [Member] | 5 [Member] | Raw Land and Lots [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	11,870	16,803
Excluding Purchased Impaired [Member] | 5 [Member] | Single Family Investment Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	8,693	9,750
Excluding Purchased Impaired [Member] | 5 [Member] | Commercial and Industrial [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	10,375	9,392
Excluding Purchased Impaired [Member] | 5 [Member] | Other Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	3,379	3,818
Excluding Purchased Impaired [Member] | 6 [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	65,704	63,672
Excluding Purchased Impaired [Member] | 6 [Member] | Commercial Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	10,730	10,906
Excluding Purchased Impaired [Member] | 6 [Member] | Commercial Real Estate - Owner Occupied [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	6,289	7,688
Excluding Purchased Impaired [Member] | 6 [Member] | Commercial Real Estate - Non-Owner Occupied [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	31,916	28,388
Excluding Purchased Impaired [Member] | 6 [Member] | Raw Land and Lots [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	4,577	4,783
Excluding Purchased Impaired [Member] | 6 [Member] | Single Family Investment Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	6,311	6,680
Excluding Purchased Impaired [Member] | 6 [Member] | Commercial and Industrial [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	4,133	4,383
Excluding Purchased Impaired [Member] | 6 [Member] | Other Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	1,748	844
Excluding Purchased Impaired [Member] | 7 [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	94,835	109,268
Excluding Purchased Impaired [Member] | 7 [Member] | Commercial Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	3,923	3,084
Excluding Purchased Impaired [Member] | 7 [Member] | Commercial Real Estate - Owner Occupied [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	18,342	15,209
Excluding Purchased Impaired [Member] | 7 [Member] | Commercial Real Estate - Non-Owner Occupied [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	18,193	31,766
Excluding Purchased Impaired [Member] | 7 [Member] | Raw Land and Lots [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	39,706	42,769
Excluding Purchased Impaired [Member] | 7 [Member] | Single Family Investment Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	6,851	7,647
Excluding Purchased Impaired [Member] | 7 [Member] | Commercial and Industrial [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	6,535	7,089
Excluding Purchased Impaired [Member] | 7 [Member] | Other Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	1,285	1,704
Excluding Purchased Impaired [Member] | 8 [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	11
Excluding Purchased Impaired [Member] | 8 [Member] | Commercial Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating
Excluding Purchased Impaired [Member] | 8 [Member] | Commercial Real Estate - Owner Occupied [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating
Excluding Purchased Impaired [Member] | 8 [Member] | Commercial Real Estate - Non-Owner Occupied [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating
Excluding Purchased Impaired [Member] | 8 [Member] | Raw Land and Lots [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating
Excluding Purchased Impaired [Member] | 8 [Member] | Single Family Investment Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating
Excluding Purchased Impaired [Member] | 8 [Member] | Commercial and Industrial [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating	11
Excluding Purchased Impaired [Member] | 8 [Member] | Other Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivables related risk rating