NON COVERED LOANS AND ALLOWANCE FOR LOAN LOSSES, Covered Loans (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended			6 Months Ended			12 Months Ended
	Jun. 30, 2011		Jun. 30, 2010	Jun. 30, 2011		Jun. 30, 2010	Dec. 31, 2010
Covered Loans [Abstract]
Percentage of total general reserve for allowance for loan losses allocated to covered loans (in hundredths)	3.10%			3.10%			1.80%
Beginning balance	$ 226,161			$ 234,633		$ 238,833	$ 238,833
Provision for loan losses	26,500		55,256	53,006		131,677	200,159
Allowance for unfunded loan commitments and letters of credit	(487)			(1,245)			(1,833)
Charge-offs	(35,595)			(73,130)			(225,203)
Recoveries	3,977			7,292			22,677
Net charge-offs	(31,618)			(65,838)		119,100	(202,526)
Ending balance	220,556			220,556			234,633
Ending balance allocated to:
Loans individually evaluated for impairment	3,746			3,746			10,024
Loans collectively evaluated for impairment	216,810			216,810			224,609
Loans acquired with deteriorated credit quality	0			0			0
Ending balance	220,556			220,556			234,633
Recorded investment in total loans receivable related to each balance in the allowance for loan losses [Abstract]
Loans individually evaluated for impairment	135,475			135,475			158,867
Loans collectively evaluated for impairment	9,811,257			9,811,257			9,120,246
Loans acquired with deteriorated credit quality	4,702,152	[1]		4,702,152	[1]		5,394,048	[1]
Ending balance	14,648,884			14,648,884			14,673,161
Residential [Member]
Covered Loans [Abstract]
Beginning balance	47,309			49,491		38,025	38,025
Provision for loan losses	(478)			446			59,525
Allowance for unfunded loan commitments and letters of credit	0			0			0
Charge-offs	(2,216)			(5,553)			(49,685)
Recoveries	15			246			1,626
Net charge-offs	(2,201)			(5,307)			(48,059)
Ending balance	44,630			44,630			49,491
Ending balance allocated to:
Loans individually evaluated for impairment	91			91			309
Loans collectively evaluated for impairment	44,539			44,539			49,182
Loans acquired with deteriorated credit quality	0			0			0
Ending balance	44,630			44,630			49,491
Residential [Member]
Recorded investment in total loans receivable related to each balance in the allowance for loan losses [Abstract]
Loans individually evaluated for impairment	23,421			23,421			24,795
Loans collectively evaluated for impairment	2,213,795			2,213,795			2,068,974
Loans acquired with deteriorated credit quality	1,473,275	[1]		1,473,275	[1]		1,614,732	[1]
Ending balance	3,710,491			3,710,491			3,708,501
Commercial Real Estate [Member]
Covered Loans [Abstract]
Beginning balance	96,221			117,752		147,591	147,591
Provision for loan losses	9,772			9,668			97,548
Allowance for unfunded loan commitments and letters of credit	0			0			0
Charge-offs	(21,985)			(44,385)			(137,460)
Recoveries	1,678			2,651			10,073
Net charge-offs	(20,307)			(41,734)			(127,387)
Ending balance	85,686			85,686			117,752
Ending balance allocated to:
Loans individually evaluated for impairment	2,081			2,081			7,247
Loans collectively evaluated for impairment	83,605			83,605			110,505
Loans acquired with deteriorated credit quality	0			0			0
Ending balance	85,686			85,686			117,752
Commercial Real Estate [Member]
Recorded investment in total loans receivable related to each balance in the allowance for loan losses [Abstract]
Loans individually evaluated for impairment	86,808			86,808			110,781
Loans collectively evaluated for impairment	3,741,821			3,741,821			3,795,957
Loans acquired with deteriorated credit quality	2,634,131	[1]		2,634,131	[1]		3,059,133	[1]
Ending balance	6,462,760			6,462,760			6,965,871
Commercial and Industrial [Member]
Covered Loans [Abstract]
Beginning balance	73,104			59,737		50,487	50,487
Provision for loan losses	15,725			37,752			34,613
Allowance for unfunded loan commitments and letters of credit	0			0			0
Charge-offs	(11,090)			(21,808)			(35,479)
Recoveries	2,246			4,304			10,116
Net charge-offs	(8,844)			(17,504)			(25,363)
Ending balance	79,985			79,985			59,737
Ending balance allocated to:
Loans individually evaluated for impairment	1,574			1,574			2,468
Loans collectively evaluated for impairment	78,411			78,411			57,269
Loans acquired with deteriorated credit quality	0			0			0
Ending balance	79,985			79,985			59,737
Commercial and Industrial [Member]
Recorded investment in total loans receivable related to each balance in the allowance for loan losses [Abstract]
Loans individually evaluated for impairment	24,169			24,169			22,671
Loans collectively evaluated for impairment	2,660,303			2,660,303			1,960,685
Loans acquired with deteriorated credit quality	519,949	[1]		519,949	[1]		634,560	[1]
Ending balance	3,204,421			3,204,421			2,617,916
Consumer [Member]
Covered Loans [Abstract]
Beginning balance	3,768			3,428		2,730	2,730
Provision for loan losses	22			1,389			2,415
Allowance for unfunded loan commitments and letters of credit	0			0			0
Charge-offs	(304)			(1,384)			(2,579)
Recoveries	38			91			862
Net charge-offs	(266)			(1,293)			(1,717)
Ending balance	3,524			3,524			3,428
Ending balance allocated to:
Loans individually evaluated for impairment	0			0			0
Loans collectively evaluated for impairment	3,524			3,524			3,428
Loans acquired with deteriorated credit quality	0			0			0
Ending balance	3,524			3,524			3,428
Consumer [Member]
Recorded investment in total loans receivable related to each balance in the allowance for loan losses [Abstract]
Loans individually evaluated for impairment	1,077			1,077			620
Loans collectively evaluated for impairment	587,863			587,863			732,905
Loans acquired with deteriorated credit quality	74,797	[1]		74,797	[1]		85,623	[1]
Ending balance	663,737			663,737			819,148
Unallocated [Member]
Covered Loans [Abstract]
Beginning balance	0			0		0	0
Provision for loan losses	487			1,245			1,833
Allowance for unfunded loan commitments and letters of credit	(487)			(1,245)			(1,833)
Charge-offs	0			0			0
Recoveries	0			0			0
Net charge-offs	0			0			0
Ending balance	0			0			0
Ending balance allocated to:
Loans individually evaluated for impairment	0			0			0
Loans collectively evaluated for impairment	0			0			0
Loans acquired with deteriorated credit quality	0			0			0
Ending balance	0			0			0
Covered Loans Subject to Allowance For Loan Losses [Member]
Recorded investment in total loans receivable related to each balance in the allowance for loan losses [Abstract]
Loans individually evaluated for impairment	0			0			0
Loans collectively evaluated for impairment	607,475			607,475			561,725
Loans acquired with deteriorated credit quality	0	[1]		0	[1]		0	[1]
Ending balance	607,475			607,475			561,725
Covered Loans Subject to Allowance For Loan Losses [Member]
Covered Loans [Abstract]
Beginning balance	5,759			4,225		0	0
Provision for loan losses	972			2,506			4,225
Allowance for unfunded loan commitments and letters of credit	0			0			0
Charge-offs	0			0			0
Recoveries	0			0			0
Net charge-offs	0			0			0
Ending balance	6,731			6,731			4,225
Ending balance allocated to:
Loans individually evaluated for impairment	0			0			0
Loans collectively evaluated for impairment	6,731			6,731			4,225
Loans acquired with deteriorated credit quality	0			0			0
Ending balance	$ 6,731			$ 6,731			$ 4,225

[1] The Company has elected to account for all covered loans acquired in the FDIC-assisted acquisitions under ASC 310-30. These are covered loans presented gross excluding the purchase discount and net of additional advances subsequent to acquisition date.