LOANS AND LEASES, Grade (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	$ 8,678,714	$ 8,636,989
Pass [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	7,952,145	7,806,414
Special Mention [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	196,947	181,808
Substandard [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	417,675	485,217
Doubtful [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	6,223	6,538
Loss [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	232	284
Impaired [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	105,492	156,728
Commercial and industrial segment [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	1,552,762	1,476,611
Commercial and industrial segment [Member] | Pass [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	1,504,523	1,426,498
Commercial and industrial segment [Member] | Special Mention [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	14,918	14,663
Commercial and industrial segment [Member] | Substandard [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	29,648	29,876
Commercial and industrial segment [Member] | Doubtful [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	531	729
Commercial and industrial segment [Member] | Impaired [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	3,142	4,845
Real estate segment [Member] | Consumer mortgages [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	1,880,338	1,873,875
Real estate segment [Member] | Home equity [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	482,068	486,074
Real estate segment [Member] | Agricultural [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	237,914	256,196
Real estate segment [Member] | Commercial and industrial-owner occupied [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	1,375,711	1,333,103
Real estate segment [Member] | Construction, acquisition and development [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	709,499	735,808
Real estate segment [Member] | Commercial real estate [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	1,754,841	1,748,881
Real estate segment [Member] | Pass [Member] | Consumer mortgages [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	1,701,566	1,691,682
Real estate segment [Member] | Pass [Member] | Home equity [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	458,379	461,151
Real estate segment [Member] | Pass [Member] | Agricultural [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	210,989	227,138
Real estate segment [Member] | Pass [Member] | Commercial and industrial-owner occupied [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	1,275,037	1,202,111
Real estate segment [Member] | Pass [Member] | Construction, acquisition and development [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	594,175	567,881
Real estate segment [Member] | Pass [Member] | Commercial real estate [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	1,537,671	1,524,262
Real estate segment [Member] | Special Mention [Member] | Consumer mortgages [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	40,526	32,840
Real estate segment [Member] | Special Mention [Member] | Home equity [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	5,391	4,791
Real estate segment [Member] | Special Mention [Member] | Agricultural [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	9,568	5,729
Real estate segment [Member] | Special Mention [Member] | Commercial and industrial-owner occupied [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	28,413	31,087
Real estate segment [Member] | Special Mention [Member] | Construction, acquisition and development [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	28,727	30,846
Real estate segment [Member] | Special Mention [Member] | Commercial real estate [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	63,791	53,455
Real estate segment [Member] | Substandard [Member] | Consumer mortgages [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	121,497	131,141
Real estate segment [Member] | Substandard [Member] | Home equity [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	15,752	17,619
Real estate segment [Member] | Substandard [Member] | Agricultural [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	13,599	17,947
Real estate segment [Member] | Substandard [Member] | Commercial and industrial-owner occupied [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	59,568	82,816
Real estate segment [Member] | Substandard [Member] | Construction, acquisition and development [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	51,041	75,031
Real estate segment [Member] | Substandard [Member] | Commercial real estate [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	117,579	120,591
Real estate segment [Member] | Doubtful [Member] | Consumer mortgages [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	2,979	2,907
Real estate segment [Member] | Doubtful [Member] | Home equity [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	698	1,057
Real estate segment [Member] | Doubtful [Member] | Commercial and industrial-owner occupied [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	222	369
Real estate segment [Member] | Doubtful [Member] | Construction, acquisition and development [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	1,025	715
Real estate segment [Member] | Doubtful [Member] | Commercial real estate [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	245	160
Real estate segment [Member] | Loss [Member] | Consumer mortgages [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	134	198
Real estate segment [Member] | Loss [Member] | Home equity [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	68	76
Real estate segment [Member] | Loss [Member] | Commercial real estate [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	30
Real estate segment [Member] | Impaired [Member] | Consumer mortgages [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	13,636	15,107
Real estate segment [Member] | Impaired [Member] | Home equity [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	1,780	1,380
Real estate segment [Member] | Impaired [Member] | Agricultural [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	3,758	5,382
Real estate segment [Member] | Impaired [Member] | Commercial and industrial-owner occupied [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	12,471	16,720
Real estate segment [Member] | Impaired [Member] | Construction, acquisition and development [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	34,531	61,335
Real estate segment [Member] | Impaired [Member] | Commercial real estate [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	35,525	50,413
Credit cards segment [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	103,251	104,884
Credit cards segment [Member] | Pass [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	103,251	104,884
All other [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	582,330	621,557
All other [Member] | Pass [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	566,554	600,807
All other [Member] | Special Mention [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	5,613	8,397
All other [Member] | Substandard [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	8,991	10,196
All other [Member] | Doubtful [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	523	601
All other [Member] | Loss [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total		10
All other [Member] | Impaired [Member]
Loan and lease portfolio, net of unearned income, by grade [Abstract]
Total	$ 649	$ 1,546