SEGMENTS (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Results of Operations [Abstract]
Net interest revenue	$ 414,591	$ 434,913	$ 441,142
Provision for credit losses	28,000	130,081	204,016
Net interest revenue, after provision for credit losses	386,591	304,832	237,126
Noninterest revenue	280,149	270,845	264,144
Noninterest expense	549,193	533,633	487,033
Income before income taxes	117,547	42,044	14,237
Income tax expense (benefit)	33,252	4,475	(8,705)
Net Income	84,295	37,569	22,942
Selected Financial Information [Abstract]
Total assets	13,397,198	12,995,851	13,615,010
Depreciation and amortization	30,942	32,214	33,672
Community Banking [Member]
Results of Operations [Abstract]
Net interest revenue	389,466	407,648	411,936
Provision for credit losses	25,482	127,794	197,539
Net interest revenue, after provision for credit losses	363,984	279,854	214,397
Noninterest revenue	113,613	126,807	114,736
Noninterest expense	351,378	338,125	308,299
Income before income taxes	126,219	68,536	20,834
Income tax expense (benefit)	39,777	40,454	2,914
Net Income	86,442	28,082	17,920
Selected Financial Information [Abstract]
Total assets	10,232,036	10,169,986	10,854,511
Depreciation and amortization	23,773	24,167	24,910
Insurance Agencies [Member]
Results of Operations [Abstract]
Net interest revenue	270	329	561
Provision for credit losses	0	0	0
Net interest revenue, after provision for credit losses	270	329	561
Noninterest revenue	90,045	86,955	82,327
Noninterest expense	78,799	73,793	70,830
Income before income taxes	11,516	13,491	12,058
Income tax expense (benefit)	4,682	5,423	4,786
Net Income	6,834	8,068	7,272
Selected Financial Information [Abstract]
Total assets	173,832	163,995	158,919
Depreciation and amortization	3,616	3,826	4,230
General Corporate and Other [Member]
Results of Operations [Abstract]
Net interest revenue	24,855	26,936	28,645
Provision for credit losses	2,518	2,287	6,477
Net interest revenue, after provision for credit losses	22,337	24,649	22,168
Noninterest revenue	76,491	57,083	67,081
Noninterest expense	119,016	121,715	107,904
Income before income taxes	(20,188)	(39,983)	(18,655)
Income tax expense (benefit)	(11,207)	(41,402)	(16,405)
Net Income	(8,981)	1,419	(2,250)
Selected Financial Information [Abstract]
Total assets	2,991,330	2,661,870	2,601,580
Depreciation and amortization	$ 3,553	$ 4,221	$ 4,532