LOANS (covered) - Covered Commercial and Consumer Credit Exposure by Risk Attribute (Detail) (USD $) In Thousands	Sep. 30, 2011	Dec. 31, 2010
Financing Receivable, Recorded Investment [Line Items]
Covered loans	$ 1,151,066	$ 1,481,493
Commercial
Financing Receivable, Recorded Investment [Line Items]
Covered loans	223,882	334,039
Commercial | Pass
Financing Receivable, Recorded Investment [Line Items]
Covered loans	133,799	225,088
Commercial | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Covered loans	25,480	35,768
Commercial | Substandard
Financing Receivable, Recorded Investment [Line Items]
Covered loans	55,429	60,090
Commercial | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Covered loans	9,174	13,093
Real estate-construction
Financing Receivable, Recorded Investment [Line Items]
Covered loans	25,893	42,743
Real estate-construction | Pass
Financing Receivable, Recorded Investment [Line Items]
Covered loans	6,116	14,021
Real estate-construction | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Covered loans	4,966	5,743
Real estate-construction | Substandard
Financing Receivable, Recorded Investment [Line Items]
Covered loans	14,811	22,979
Real estate-construction | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Covered loans	0	0
Real estate-commercial
Financing Receivable, Recorded Investment [Line Items]
Covered loans	687,392	855,725
Real estate-commercial | Pass
Financing Receivable, Recorded Investment [Line Items]
Covered loans	370,605	476,140
Real estate-commercial | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Covered loans	77,308	106,057
Real estate-commercial | Substandard
Financing Receivable, Recorded Investment [Line Items]
Covered loans	235,316	268,651
Real estate-commercial | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Covered loans	4,163	4,877
Real estate-residential
Financing Receivable, Recorded Investment [Line Items]
Covered loans	127,753	147,052
Real estate-residential | Performing
Financing Receivable, Recorded Investment [Line Items]
Covered loans	127,753	147,052
Real estate-residential | Nonperforming
Financing Receivable, Recorded Investment [Line Items]
Covered loans	0	0
Installment
Financing Receivable, Recorded Investment [Line Items]
Covered loans	14,178	21,071
Installment | Performing
Financing Receivable, Recorded Investment [Line Items]
Covered loans	14,178	21,071
Installment | Nonperforming
Financing Receivable, Recorded Investment [Line Items]
Covered loans	0	0
Home equity
Financing Receivable, Recorded Investment [Line Items]
Covered loans	67,897	73,695
Home equity | Performing
Financing Receivable, Recorded Investment [Line Items]
Covered loans	65,783	72,204
Home equity | Nonperforming
Financing Receivable, Recorded Investment [Line Items]
Covered loans	2,114	1,491
All other
Financing Receivable, Recorded Investment [Line Items]
Covered loans	4,071	7,168
All other | Performing
Financing Receivable, Recorded Investment [Line Items]
Covered loans	4,071	7,168
All other | Nonperforming
Financing Receivable, Recorded Investment [Line Items]
Covered loans	$ 0	$ 0