LOANS AND LEASES (Non-Performing Loans And Leases) (Details) - USD ($) $ in Thousands	3 Months Ended
	Jun. 30, 2017	Dec. 31, 2016	Jun. 30, 2016
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	$ 11,018,540	$ 10,811,991	$ 10,575,978
Non-accrual loans and leases	$ 63,585	71,812	68,638
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	$ 63,585	71,812	68,638
Total	71,681	101,842	80,200
Non-Performing [Member] | 90+ Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Still accruing	1,793	3,983	1,875
Non-Performing [Member] | Restructured Loans And Leases [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Still accruing	6,303	26,047	9,687
Commercial And Industrial [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	1,566,459	1,612,295
Non-accrual loans and leases	9,988	13,679	8,675
Real Estate [Member] | Consumer Mortgages [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	2,776,213	2,643,966
Non-accrual loans and leases	24,690	21,084	19,309
Real Estate [Member] | Home Equity [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	624,868	628,846
Non-accrual loans and leases	3,183	3,817	2,734
Real Estate [Member] | Agricultural [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	245,646	245,377
Non-accrual loans and leases	6,172	1,546	1,107
Real Estate [Member] | Commercial And Industrial - Owner Occupied [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	1,795,321	1,764,265
Non-accrual loans and leases	10,215	10,791	16,021
Real Estate [Member] | Construction, Acquisition And Development [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	1,156,901	1,157,248
Non-accrual loans and leases	2,223	7,022	6,086
Real Estate [Member] | Commercial Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	2,341,633	2,237,719
Non-accrual loans and leases	6,418	13,402	14,197
Credit Cards [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	104,169	109,656
Non-accrual loans and leases	122	161	159
All Other [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	407,330	412,619
Non-accrual loans and leases	$ 574	$ 310	$ 350