ALLOWANCE FOR CREDIT LOSSES (Changes In The Allowance For Credit Losses By Segment And Class) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended		12 Months Ended
	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance at beginning of period		$ 126,458	$ 142,443	$ 142,443
Charge-offs		(11,333)	(17,171)	(26,719)
Recoveries		7,762	20,737	23,734
Provision	$ (3,000)	3,000	(13,000)	(13,000)
Balance at end of period	133,009	125,887	133,009	126,458
Commercial And Industrial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance at beginning of period		17,583	21,419	21,419
Charge-offs		(2,068)	(3,829)	(10,022)
Recoveries		814	1,681	2,035
Provision		1,516	4,559	4,151
Balance at end of period	23,830	17,845	23,830	17,583
Real Estate [Member] | Consumer Mortgages [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance at beginning of period		33,198	40,015	40,015
Charge-offs		(1,782)	(2,849)	(3,995)
Recoveries		1,281	2,113	2,693
Provision		(1,078)	(5,635)	(5,515)
Balance at end of period	33,644	31,619	33,644	33,198
Real Estate [Member] | Home Equity [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance at beginning of period		6,949	9,542	9,542
Charge-offs		(1,011)	(1,057)	(1,204)
Recoveries		435	516	639
Provision		1,674	(1,039)	(2,028)
Balance at end of period	7,962	8,047	7,962	6,949
Real Estate [Member] | Agricultural [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance at beginning of period		2,524	3,420	3,420
Charge-offs		(110)	(17)	(33)
Recoveries		160	364	384
Provision		(422)	(1,252)	(1,247)
Balance at end of period	2,515	2,152	2,515	2,524
Real Estate [Member] | Commercial And Industrial - Owner Occupied [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance at beginning of period		14,607	16,325	16,325
Charge-offs		(1,075)	(1,443)	(1,800)
Recoveries		343	2,527	2,834
Provision		(1,090)	(2,452)	(2,752)
Balance at end of period	14,957	12,785	14,957	14,607
Real Estate [Member] | Construction, Acquisition And Development [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance at beginning of period		15,925	9,885	9,885
Charge-offs		(511)	(818)	(1,039)
Recoveries		1,178	10,666	11,727
Provision		(3,015)	(8,933)	(4,648)
Balance at end of period	10,800	13,577	10,800	15,925
Real Estate [Member] | Commercial Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance at beginning of period		25,508	23,562	23,562
Charge-offs		(1,129)	(3,601)	(3,723)
Recoveries		2,235	1,507	1,656
Provision		233	3,637	4,013
Balance at end of period	25,105	26,847	25,105	25,508
Credit Cards [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance at beginning of period		4,047	6,514	6,514
Charge-offs		(2,030)	(1,909)	(2,632)
Recoveries		642	506	658
Provision		4,459	(221)	(493)
Balance at end of period	4,890	7,118	4,890	4,047
All Other [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance at beginning of period		6,117	11,761	11,761
Charge-offs		(1,617)	(1,648)	(2,271)
Recoveries		674	857	1,108
Provision		723	(1,664)	(4,481)
Balance at end of period	$ 9,306	$ 5,897	$ 9,306	$ 6,117