BUSINESS SEGMENTS (Details 2) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011	Dec. 31, 2011
Segment Reporting Information
Interest income	$ 254,162	$ 282,741	$ 774,574	$ 811,544
Charge for funds used	(37,954)	(53,712)	(122,606)	(180,442)
Interest spread on funds used	216,208	229,029	651,968	631,102
Interest expense	(32,254)	(44,959)	(100,591)	(137,592)
Credit on funds provided	37,954	53,712	122,606	180,442
Interest spread on funds provided	5,700	8,753	22,015	42,850
Net interest income before provision for loan losses	221,908	237,782	673,983	673,952
Provision for loan losses	18,500	22,000	52,100	75,006	95,006
Depreciation, amortization and accretion	4,669	16,670	49,343	100,082
Goodwill	337,438	337,438	337,438	337,438	337,438
Segment pre-tax profit (loss)	105,203	97,685	317,392	279,995
Segment assets	21,813,165	21,813,046	21,813,165	21,813,046	21,968,667
Retail Banking
Segment Reporting Information
Interest income	87,603	88,189	266,224	270,943
Charge for funds used	(20,983)	(22,394)	(65,392)	(72,073)
Interest spread on funds used	66,620	65,795	200,832	198,870
Interest expense	(13,986)	(21,407)	(43,752)	(67,515)
Credit on funds provided	31,231	46,480	100,002	158,212
Interest spread on funds provided	17,245	25,073	56,250	90,697
Net interest income before provision for loan losses	83,865	90,868	257,082	289,567
Provision for loan losses	12,097	11,185	29,385	20,128
Depreciation, amortization and accretion	2,001	6,815	16,401	34,941
Goodwill	320,566	320,566	320,566	320,566
Segment pre-tax profit (loss)	14,223	15,773	54,465	81,443
Segment assets	6,366,341	6,230,680	6,366,341	6,230,680
Commercial Lending
Segment Reporting Information
Interest income	151,458	166,789	446,572	465,138
Charge for funds used	(29,088)	(33,575)	(88,759)	(111,128)
Interest spread on funds used	122,370	133,214	357,813	354,010
Interest expense	(5,959)	(9,248)	(18,221)	(23,236)
Credit on funds provided	3,115	3,291	9,531	10,225
Interest spread on funds provided	(2,844)	(5,957)	(8,690)	(13,011)
Net interest income before provision for loan losses	119,526	127,257	349,123	340,999
Provision for loan losses	6,403	10,815	22,715	54,878
Depreciation, amortization and accretion	(6,979)	2,912	3,679	51,012
Goodwill	16,872	16,872	16,872	16,872
Segment pre-tax profit (loss)	73,168	64,290	196,852	164,258
Segment assets	10,121,984	10,345,990	10,121,984	10,345,990
Other
Segment Reporting Information
Interest income	15,101	27,763	61,778	75,463
Charge for funds used	12,117	2,257	31,545	2,759
Interest spread on funds used	27,218	30,020	93,323	78,222
Interest expense	(12,309)	(14,304)	(38,618)	(46,841)
Credit on funds provided	3,608	3,941	13,073	12,005
Interest spread on funds provided	(8,701)	(10,363)	(25,545)	(34,836)
Net interest income before provision for loan losses	18,517	19,657	67,778	43,386
Depreciation, amortization and accretion	9,647	6,943	29,263	14,129
Segment pre-tax profit (loss)	17,812	17,622	66,075	34,294
Segment assets	$ 5,324,840	$ 5,236,376	$ 5,324,840	$ 5,236,376