ALLOWANCE FOR CREDIT LOSSES (1) (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011	Sep. 30, 2011	Dec. 31, 2010
Financing Receivable, Impaired [Line Items]
Recorded balance of impaired loans	$ 176,139	$ 234,923
Allowance for impaired loans and leases	18,205	39,708
Allowance for all other loans and leases	150,814	155,410
Total allowance	169,019	195,118	199,686	196,913
Construction, acquisition and development [Member]
Financing Receivable, Impaired [Line Items]
Recorded balance of impaired loans	87,753	128,179
Allowance for impaired loans and leases	10,179	21,581
Commercial and industrial segment [Member]
Financing Receivable, Impaired [Line Items]
Recorded balance of impaired loans	6,219	7,833
Allowance for impaired loans and leases	2,025	4,071
Allowance for all other loans and leases	19,680	16,653
Total allowance	21,705	20,724	20,024	22,479
Real estate [Member] | Consumer mortgages [Member]
Financing Receivable, Impaired [Line Items]
Recorded balance of impaired loans	15,854	31,793
Allowance for impaired loans and leases	1,338	4,386
Allowance for all other loans and leases	26,878	32,143
Total allowance	28,216	36,529	39,501	35,540
Real estate [Member] | Home equity [Member]
Financing Receivable, Impaired [Line Items]
Recorded balance of impaired loans	1,638	675
Allowance for impaired loans and leases	363	48
Allowance for all other loans and leases	5,558	8,582
Total allowance	5,921	8,630	9,888	7,305
Real estate [Member] | Agricultural [Member]
Financing Receivable, Impaired [Line Items]
Recorded balance of impaired loans	5,562	3,096
Allowance for impaired loans and leases	331	380
Allowance for all other loans and leases	2,323	3,541
Total allowance	2,654	3,921	4,392	4,997
Real estate [Member] | Commercial and industrial-owner occupied [Member]
Financing Receivable, Impaired [Line Items]
Recorded balance of impaired loans	20,989	24,801
Allowance for impaired loans and leases	696	3,601
Allowance for all other loans and leases	18,623	18,328
Total allowance	19,319	21,929	21,470	20,403
Real estate [Member] | Construction, acquisition and development [Member]
Financing Receivable, Impaired [Line Items]
Recorded balance of impaired loans	87,753	128,179
Allowance for impaired loans and leases	10,179	21,581
Allowance for all other loans and leases	22,363	23,981
Total allowance	32,542	45,562	48,238	59,048
Real estate [Member] | Commercial Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Recorded balance of impaired loans	37,202	36,122
Allowance for impaired loans and leases	3,213	5,324
Allowance for all other loans and leases	38,958	34,120
Total allowance	42,171	39,444	39,563	33,439
Credit cards segment [Member]
Financing Receivable, Impaired [Line Items]
Recorded balance of impaired loans	0	0
Allowance for impaired loans and leases	0	0
Allowance for all other loans and leases	3,169	4,021
Total allowance	3,169	4,021	3,920	4,126
All other receivables [Member]
Financing Receivable, Impaired [Line Items]
Recorded balance of impaired loans	922	2,424
Allowance for impaired loans and leases	60	317
Allowance for all other loans and leases	13,262	14,041
Total allowance	$ 13,322	$ 14,358	$ 12,690	$ 9,576