NON-COVERED LOANS AND ALLOWANCE FOR LOAN LOSSES (Impairment Methodology) (Details) (USD $) In Thousands	Sep. 30, 2011		Dec. 31, 2010
Recorded investment in total loans receivable related to each balance in the allowance for loan losses [Abstract]
Loans individually evaluated for impairment	$ 207,962		$ 281,006
Loans collectively evaluated for impairment	10,185,892		8,998,107
Loans acquired with deteriorated credit quality	4,431,663	[1]	5,394,048	[1]
Ending balance	14,825,517		14,673,161
Residential [Member]
Recorded investment in total loans receivable related to each balance in the allowance for loan losses [Abstract]
Loans individually evaluated for impairment	44,726		51,519
Loans collectively evaluated for impairment	2,415,656		2,068,974
Loans acquired with deteriorated credit quality	1,401,215	[1]	1,614,732	[1]
Ending balance	3,861,597		3,708,501
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	134,799		201,926
Loans collectively evaluated for impairment	3,696,342		3,704,812
Loans acquired with deteriorated credit quality	2,487,186	[1]	3,059,133	[1]
Ending balance	6,318,327		6,965,871
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	25,585		26,941
Loans collectively evaluated for impairment	2,986,567		1,956,415
Loans acquired with deteriorated credit quality	471,994	[1]	634,560	[1]
Ending balance	3,484,146		2,617,916
Consumer [Member]
Recorded investment in total loans receivable related to each balance in the allowance for loan losses [Abstract]
Loans individually evaluated for impairment	2,852		620
Loans collectively evaluated for impairment	500,723		732,905
Loans acquired with deteriorated credit quality	71,268	[1]	85,623	[1]
Ending balance	574,843		819,148
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
Loans collectively evaluated for impairment	586,604		561,725
Loans acquired with deteriorated credit quality	0	[1]	0	[1]
Ending balance	$ 586,604		$ 561,725

[1] The Company has elected to account for all covered loans acquired in the FDIC-assisted acquisitions under ASC 310-30. The total principal balance is presented and excludes the purchase discount and any additional advances subsequent to acquisition date.