SEGMENT REPORTING (Details) (USD $) In Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010	Dec. 31, 2010
Results of Operations [Abstract]
Net interest revenue	$ 108,075	$ 109,678	$ 327,424	$ 330,889
Provision for credit losses	25,112	54,850	110,831	160,723
Net interest revenue after provision for credit losses	82,963	54,828	216,593	170,166
Noninterest revenue	62,055	69,752	205,510	190,170
Noninterest expense	130,698	123,087	397,777	363,586
Income (loss) before income taxes	14,320	1,493	24,326	(3,250)
Income tax expense (benefit)	2,386	(9,767)	60	(10,346)
Net income (loss)	11,934	11,260	24,266	7,096
Selected Financial Information [Abstract]
Total assets at end of period	13,198,518	13,583,016	13,198,518	13,583,016	13,615,010	[1]
Depreciation and amortization	7,987	8,330	24,460	25,230
Community Banking [Member]
Results of Operations [Abstract]
Net interest revenue	101,092	102,420	306,635	308,942
Provision for credit losses	23,416	54,609	109,191	155,346
Net interest revenue after provision for credit losses	77,676	47,811	197,444	153,596
Noninterest revenue	30,940	31,372	99,845	87,347
Noninterest expense	83,028	72,387	257,683	229,144
Income (loss) before income taxes	25,588	6,796	39,606	11,799
Income tax expense (benefit)	5,669	3,837	13,313	483
Net income (loss)	19,919	2,959	26,293	11,316
Selected Financial Information [Abstract]
Total assets at end of period	10,305,304	10,770,259	10,305,304	10,770,259
Depreciation and amortization	5,967	6,164	18,348	18,637
Insurance Agencies [Member]
Results of Operations [Abstract]
Net interest revenue	79	151	258	444
Provision for credit losses	0	0	0	0
Net interest revenue after provision for credit losses	79	151	258	444
Noninterest revenue	22,009	20,815	67,436	64,174
Noninterest expense	19,032	17,633	56,095	53,111
Income (loss) before income taxes	3,056	3,333	11,599	11,507
Income tax expense (benefit)	1,238	1,334	4,639	4,572
Net income (loss)	1,818	1,999	6,960	6,935
Selected Financial Information [Abstract]
Total assets at end of period	166,572	157,388	166,572	157,388
Depreciation and amortization	947	1,042	2,893	3,206
General Corporate and Other [Member]
Results of Operations [Abstract]
Net interest revenue	6,904	7,107	20,531	21,503
Provision for credit losses	1,696	241	1,640	5,377
Net interest revenue after provision for credit losses	5,208	6,866	18,891	16,126
Noninterest revenue	9,106	17,565	38,229	38,649
Noninterest expense	28,638	33,067	83,999	81,331
Income (loss) before income taxes	(14,324)	(8,636)	(26,879)	(26,556)
Income tax expense (benefit)	(4,521)	(14,938)	(17,892)	(15,401)
Net income (loss)	(9,803)	6,302	(8,987)	(11,155)
Selected Financial Information [Abstract]
Total assets at end of period	2,726,642	2,655,369	2,726,642	2,655,369
Depreciation and amortization	$ 1,073	$ 1,124	$ 3,219	$ 3,387

[1] Derived from audited financial statements.