LOANS AND LEASES, Non-performing and Nonaccrual Loans and Leases (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Dec. 31, 2011	Mar. 31, 2011
Non-performing loans and leases [Abstract]
Non-accrual loans and leases	$ 253,227	$ 276,798	$ 370,726
Loans and leases 90 days or more past due, still accruing	1,698	3,434	4,829
Restructured loans and leases still accruing	30,311	42,018	49,472
Total non-performing loans and leases	285,236	322,250	425,027
Days past due of principal or interest at which loans and leases may be placed in non-accrual status (in days)	90D
Nonaccrual loans and leases [Abstract]
Non-accrual loans and leases	253,227	276,798	370,726
Commercial and industrial segment [Member]
Non-performing loans and leases [Abstract]
Non-accrual loans and leases	11,025	12,260	14,655
Loans and leases 90 days or more past due, still accruing	10	12
Nonaccrual loans and leases [Abstract]
Non-accrual loans and leases	11,025	12,260	14,655
Real estate segment [Member] | Consumer mortgages [Member]
Non-performing loans and leases [Abstract]
Non-accrual loans and leases	46,562	47,878	58,748
Loans and leases 90 days or more past due, still accruing	1,314	2,974
Nonaccrual loans and leases [Abstract]
Non-accrual loans and leases	46,562	47,878	58,748
Real estate segment [Member] | Home equity [Member]
Non-performing loans and leases [Abstract]
Non-accrual loans and leases	2,687	2,036	1,543
Loans and leases 90 days or more past due, still accruing	0	0
Nonaccrual loans and leases [Abstract]
Non-accrual loans and leases	2,687	2,036	1,543
Real estate segment [Member] | Agricultural [Member]
Non-performing loans and leases [Abstract]
Non-accrual loans and leases	4,254	4,179	7,597
Loans and leases 90 days or more past due, still accruing	0	0
Nonaccrual loans and leases [Abstract]
Non-accrual loans and leases	4,254	4,179	7,597
Real estate segment [Member] | Commercial and industrial-owner occupied [Member]
Non-performing loans and leases [Abstract]
Non-accrual loans and leases	32,842	33,112	24,638
Loans and leases 90 days or more past due, still accruing	0	0
Nonaccrual loans and leases [Abstract]
Non-accrual loans and leases	32,842	33,112	24,638
Real estate segment [Member] | Construction, acquisition and development [Member]
Non-performing loans and leases [Abstract]
Non-accrual loans and leases	115,649	133,110	202,124
Loans and leases 90 days or more past due, still accruing	0	0
Nonaccrual loans and leases [Abstract]
Non-accrual loans and leases	115,649	133,110	202,124
Real estate segment [Member] | Commercial [Member]
Non-performing loans and leases [Abstract]
Non-accrual loans and leases	35,715	40,616	58,945
Loans and leases 90 days or more past due, still accruing	0	0
Nonaccrual loans and leases [Abstract]
Non-accrual loans and leases	35,715	40,616	58,945
Credit cards segment [Member]
Non-performing loans and leases [Abstract]
Non-accrual loans and leases	509	594	617
Loans and leases 90 days or more past due, still accruing	228	299
Nonaccrual loans and leases [Abstract]
Non-accrual loans and leases	509	594	617
All other receivables [Member]
Non-performing loans and leases [Abstract]
Non-accrual loans and leases	3,984	3,013	1,859
Loans and leases 90 days or more past due, still accruing	146	149
Nonaccrual loans and leases [Abstract]
Non-accrual loans and leases	$ 3,984	$ 3,013	$ 1,859