FDIC Indemnification Asset (Detail) (USD $)	3 Months Ended
	Mar. 31, 2013
FDIC Loss On Loans To FDIC Indemnification Asset	$ 3,300,000
FDIC Indemnification Asset, Cash Payments Received	21,200,000
Payments From FDIC Credited to OREO Expenses	488,000
Claims With FDIC Under Loss Share Agreement	8,800,000
Assumption Of Loss [Member] | Cape Fear [Member]
FDIC Indemnification Asset Losses	32,400,000
Cape Fear [Member]
FDIC Indemnification Asset Losses	110,000,000
FDIC Indemnification Asset Reimbursement Rate	80.00%
FDIC reimbursements Amount	32,400,000
FDIC Indemnification Asset Reimbursement Rate1	95.00%
Plantation [Member]
FDIC Indemnification Asset Losses	55,000,000
FDIC Indemnification Asset Reimbursement Rate	80.00%
FDIC reimbursements Amount	$ 65,000,000
FDIC Indemnification Asset Reimbursement Rate1	60.00%