ALLOWANCE FOR LOAN AND LEASE LOSSES - Allowance for Loan and Lease Losses on Covered Loans for the Previous Five Quarters (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended					9 Months Ended
	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Receivables [Abstract]
FDIC Indemnification Income	$ 8,496				$ 8,377	$ 29,592	$ 53,455
Balance at beginning of period	48,327	46,156	42,835	48,112	51,044	42,835	16,493
Provision for loan and lease losses	6,622	6,047	12,951	6,910	7,260	25,620	57,171
Loans charged-off	(9,058)	(5,163)	(10,118)	(13,513)	(10,609)	(24,339)	(32,091)
Recoveries	3,004	1,287	488	1,326	417	4,779	6,539
Balance at end of period	$ 48,895	$ 48,327	$ 46,156	$ 42,835	$ 48,112	$ 48,895	$ 48,112