BUSINESS SEGMENTS (Details 2) (USD $)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012
Segment Reporting Information
Interest income	$ 255,353,000	$ 266,362,000	$ 493,776,000	$ 520,412,000
Charge for funds used	(45,628,000)	(41,563,000)	(84,412,000)	(84,652,000)
Interest spread on funds used	209,725,000	224,799,000	409,364,000	435,760,000
Interest expense	(27,709,000)	(33,205,000)	(56,841,000)	(68,337,000)
Credit on funds provided	45,628,000	41,563,000	84,412,000	84,652,000
Interest spread on funds provided	17,919,000	8,358,000	27,571,000	16,315,000
Net interest income	227,644,000	233,157,000	436,935,000	452,075,000
Provision for loan losses	9,000,000	15,500,000	13,327,000	33,600,000	65,184,000
Depreciation, amortization and accretion	23,912,000	6,005,000	38,909,000	44,674,000
Goodwill	337,438,000	337,438,000	337,438,000	337,438,000	337,438,000
Segment pre-tax profit (loss)	111,870,000	104,394,000	218,380,000	212,189,000
Segment assets	23,308,406,000	21,525,734,000	23,308,406,000	21,525,734,000	22,536,110,000
Retail Banking
Segment Reporting Information
Interest income	93,928,000	92,369,000	176,767,000	178,622,000
Charge for funds used	(17,901,000)	(22,149,000)	(37,885,000)	(44,409,000)
Interest spread on funds used	76,027,000	70,220,000	138,882,000	134,213,000
Interest expense	(11,708,000)	(14,218,000)	(24,353,000)	(29,766,000)
Credit on funds provided	36,022,000	33,731,000	68,418,000	68,771,000
Interest spread on funds provided	24,314,000	19,513,000	44,065,000	39,005,000
Net interest income	100,341,000	89,733,000	182,947,000	173,218,000
Provision for loan losses	2,886,000	10,375,000	6,566,000	17,289,000
Depreciation, amortization and accretion	5,865,000	2,466,000	8,286,000	14,399,000
Goodwill	320,566,000	320,566,000	320,566,000	320,566,000
Segment pre-tax profit (loss)	32,493,000	18,483,000	51,420,000	40,242,000
Segment assets	7,035,908,000	6,516,382,000	7,035,908,000	6,516,382,000
Commercial Banking
Segment Reporting Information
Interest income	147,168,000	152,148,000	287,228,000	295,113,000
Charge for funds used	(27,883,000)	(29,922,000)	(55,956,000)	(59,671,000)
Interest spread on funds used	119,285,000	122,226,000	231,272,000	235,442,000
Interest expense	(3,940,000)	(5,196,000)	(8,317,000)	(12,262,000)
Credit on funds provided	5,711,000	3,292,000	9,334,000	6,416,000
Interest spread on funds provided	1,771,000	(1,904,000)	1,017,000	(5,846,000)
Net interest income	121,056,000	120,322,000	232,289,000	229,596,000
Provision for loan losses	6,114,000	5,125,000	6,761,000	16,311,000
Depreciation, amortization and accretion	3,445,000	(6,474,000)	626,000	10,658,000
Goodwill	16,872,000	16,872,000	16,872,000	16,872,000
Segment pre-tax profit (loss)	65,514,000	63,257,000	132,195,000	123,684,000
Segment assets	10,903,753,000	10,058,264,000	10,903,753,000	10,058,264,000
Other
Segment Reporting Information
Interest income	14,257,000	21,845,000	29,781,000	46,677,000
Charge for funds used	156,000	10,508,000	9,429,000	19,428,000
Interest spread on funds used	14,413,000	32,353,000	39,210,000	66,105,000
Interest expense	(12,061,000)	(13,791,000)	(24,171,000)	(26,309,000)
Credit on funds provided	3,895,000	4,540,000	6,660,000	9,465,000
Interest spread on funds provided	(8,166,000)	(9,251,000)	(17,511,000)	(16,844,000)
Net interest income	6,247,000	23,102,000	21,699,000	49,261,000
Depreciation, amortization and accretion	14,602,000	10,013,000	29,997,000	19,617,000
Segment pre-tax profit (loss)	13,863,000	22,654,000	34,765,000	48,263,000
Segment assets	$ 5,368,745,000	$ 4,951,088,000	$ 5,368,745,000	$ 4,951,088,000