LOANS AND LEASES (Non-Performing Loans And Leases) (Details) - USD ($) $ in Thousands	3 Months Ended
	Sep. 30, 2017	Dec. 31, 2016	Sep. 30, 2016
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	$ 11,055,509	$ 10,811,991	$ 10,658,761
Non-accrual loans and leases	$ 55,796	71,812	70,725
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	$ 55,796	71,812	70,725
Total	65,017	101,842	90,916
Non-Performing [Member] | 90+ Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Still accruing	1,855	3,983	2,255
Non-Performing [Member] | Restructured Loans And Leases [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Still accruing	7,366	26,047	17,936
Commercial And Industrial [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	1,506,352	1,612,295
Non-accrual loans and leases	8,776	13,679	11,659
Real Estate [Member] | Consumer Mortgages [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	2,826,333	2,643,966
Non-accrual loans and leases	23,635	21,084	20,196
Real Estate [Member] | Home Equity [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	626,961	628,846
Non-accrual loans and leases	2,555	3,817	3,721
Real Estate [Member] | Agricultural [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	247,211	245,377
Non-accrual loans and leases	5,919	1,546	1,194
Real Estate [Member] | Commercial And Industrial - Owner Occupied [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	1,835,430	1,764,265
Non-accrual loans and leases	7,558	10,791	11,983
Real Estate [Member] | Construction, Acquisition And Development [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	1,175,979	1,157,248
Non-accrual loans and leases	1,771	7,022	6,939
Real Estate [Member] | Commercial Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	2,336,219	2,237,719
Non-accrual loans and leases	4,645	13,402	14,793
Credit Cards [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	104,613	109,656
Non-accrual loans and leases	126	161	121
All Other [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	396,411	412,619
Non-accrual loans and leases	$ 811	$ 310	$ 119