ALLOWANCE FOR CREDIT LOSSES (Changes In The Allowance For Credit Losses By Segment And Class) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		12 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Changes in the allowance for credit losses [Roll Forward]
Balance at beginning of period	$ 142,443	$ 153,236	$ 153,236
Charge-offs	(4,780)	(8,075)	(25,027)
Recoveries	3,997	4,543	14,234
Provision	(5,000)
Balance at end of period	136,660	149,704	142,443
Commercial And Industrial [Member]
Changes in the allowance for credit losses [Roll Forward]
Balance at beginning of period	21,419	18,376	18,376
Charge-offs	(383)	(201)	(2,546)
Recoveries	502	1,076	2,298
Provision	(517)	(337)	3,291
Balance at end of period	21,021	18,914	21,419
Real Estate [Member] | Consumer Mortgages [Member]
Changes in the allowance for credit losses [Roll Forward]
Balance at beginning of period	40,015	39,525	39,525
Charge-offs	(892)	(1,945)	(6,037)
Recoveries	612	538	3,267
Provision	(664)	210	3,260
Balance at end of period	39,071	38,328	40,015
Real Estate [Member] | Home Equity [Member]
Changes in the allowance for credit losses [Roll Forward]
Balance at beginning of period	9,542	5,663	5,663
Charge-offs	(498)	(318)	(1,359)
Recoveries	241	184	625
Provision	261	183	4,613
Balance at end of period	9,546	5,712	9,542
Real Estate [Member] | Agricultural [Member]
Changes in the allowance for credit losses [Roll Forward]
Balance at beginning of period	3,420	2,800	2,800
Charge-offs	(8)	(696)	(765)
Recoveries	269	9	96
Provision	(535)	721	1,289
Balance at end of period	3,146	2,834	3,420
Real Estate [Member] | Commercial And Industrial - Owner Occupied [Member]
Changes in the allowance for credit losses [Roll Forward]
Balance at beginning of period	16,325	17,059	17,059
Charge-offs	(394)	(1,206)	(3,591)
Recoveries	550	358	1,112
Provision	(817)	350	1,745
Balance at end of period	15,664	16,561	16,325
Real Estate [Member] | Construction, Acquisition And Development [Member]
Changes in the allowance for credit losses [Roll Forward]
Balance at beginning of period	9,885	11,828	11,828
Charge-offs	(343)	(1,666)	(3,731)
Recoveries	604	1,637	3,734
Provision	(233)	(1,479)	(1,946)
Balance at end of period	9,913	10,320	9,885
Real Estate [Member] | Commercial Real Estate [Member]
Changes in the allowance for credit losses [Roll Forward]
Balance at beginning of period	23,562	43,853	43,853
Charge-offs	(1,007)	(901)	(1,795)
Recoveries	720	323	1,458
Provision	(1,773)	1,496	(19,954)
Balance at end of period	21,502	44,771	23,562
Credit Cards [Member]
Changes in the allowance for credit losses [Roll Forward]
Balance at beginning of period	6,514	3,782	3,782
Charge-offs	(676)	(559)	(2,359)
Recoveries	153	131	542
Provision	(672)	(868)	4,549
Balance at end of period	5,319	2,486	6,514
All Other [Member]
Changes in the allowance for credit losses [Roll Forward]
Balance at beginning of period	11,761	10,350	10,350
Charge-offs	(579)	(583)	(2,844)
Recoveries	346	287	1,102
Provision	(50)	(276)	3,153
Balance at end of period	$ 11,478	$ 9,778	$ 11,761