LOANS AND LEASES (Non-Performing Loans And Leases) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Dec. 31, 2016	Mar. 31, 2016
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	$ 10,801,694	$ 10,811,991	$ 10,444,697
Non-accrual loans and leases	$ 74,439	71,812	81,926
Days past due of principal or interest at which loans and leases may be placed in non-accrual status	90 days
Non-Performing [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-accrual loans and leases	$ 74,439	71,812	81,926
Total	81,562	101,842	94,246
Non-Performing [Member] | 90+ Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Still accruing	3,063	3,983	4,567
Non-Performing [Member] | Restructured Loans And Leases [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Still accruing	4,060	26,047	7,753
Commercial And Industrial [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	1,536,527	1,612,295
Non-accrual loans and leases	13,959	13,679	10,248
Real Estate [Member] | Consumer Mortgages [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	2,675,672	2,643,966
Non-accrual loans and leases	21,543	21,084	22,968
Real Estate [Member] | Home Equity [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	626,488	628,846
Non-accrual loans and leases	3,157	3,817	3,564
Real Estate [Member] | Agricultural [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	240,534	245,377
Non-accrual loans and leases	5,180	1,546	932
Real Estate [Member] | Commercial And Industrial - Owner Occupied [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	1,801,613	1,764,265
Non-accrual loans and leases	15,135	10,791	16,633
Real Estate [Member] | Construction, Acquisition And Development [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	1,136,827	1,157,248
Non-accrual loans and leases	1,466	7,022	7,720
Real Estate [Member] | Commercial Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	2,271,542	2,237,719
Non-accrual loans and leases	13,638	13,402	19,417
Credit Cards [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	103,813	109,656
Non-accrual loans and leases	87	161	188
All Other [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	408,678	412,619
Non-accrual loans and leases	$ 274	$ 310	$ 256