Summary of Significant Accounting Policies - Additional Information (Detail) (USD $) Share data in Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014 shareholder	Dec. 31, 2013	Dec. 31, 2012	May 25, 2012	Nov. 01, 2014
Summary Of Significant Accounting Policies [Line Items]
Shareholders require to qualify REIT	100
Percentage of preferred stock issued by each REIT	20.00%
Common stock dividend rate, percentage				5.00%
Cash reserve or deposits	$ 45,500,000	$ 58,200,000
OREO and repossessed assets total	24,700,000	38,300,000
Foreclosed assets acquired in FDIC-assisted transactions	9,200,000	12,300,000
First tranche reimbursement percentage from bank to FDIC	80.00%
FDIC loss-share receivable	13,848,000	32,757,000	44,996,000
Anti-dilutive common stock options and warrants	6.2	6.7	7.2
Minimum [Member]
Summary Of Significant Accounting Policies [Line Items]
Premises and equipment, useful life	3 years
Maximum [Member]
Summary Of Significant Accounting Policies [Line Items]
Premises and equipment, useful life	40 years
First United Bancorp, Inc. [Member]
Summary Of Significant Accounting Policies [Line Items]
FDIC loss-share receivable	6,900,000
LibertyPointe Bank Acquisition [Member]
Summary Of Significant Accounting Policies [Line Items]
FDIC loss share coverage percentage up to first tranche	80.00%
FDIC loss share recovery limit first tranche	55,000,000
Portion of first loss tranche ineligible for FDIC reimbursement	11,700,000
FDIC loss share coverage percentage up to first tranche	95.00%
Park Avenue Bank Acquisition [Member]
Summary Of Significant Accounting Policies [Line Items]
FDIC loss share coverage percentage up to first tranche	80.00%
FDIC loss share recovery limit first tranche	66,000,000
FDIC loss share coverage percentage up to first tranche	95.00%
Residential Mortgage [Member]
Summary Of Significant Accounting Policies [Line Items]
Loans held for sale (1)	17,200,000
Non-Performing Commercial Real Estate [Member]
Summary Of Significant Accounting Policies [Line Items]
Loans held for sale (1)	7,100,000
Commercial loans [Member] | Minimum [Member]
Summary Of Significant Accounting Policies [Line Items]
Number of days past due of loans to be full or partial charged-off	90 days
Commercial loans [Member] | Maximum [Member]
Summary Of Significant Accounting Policies [Line Items]
Number of days past due of loans to be full or partial charged-off	120 days
Residential loans and home equity loans [Member]
Summary Of Significant Accounting Policies [Line Items]
Number of days past due of loans to be full or partial charged-off	120 days
Automobile loans [Member]
Summary Of Significant Accounting Policies [Line Items]
Number of days past due of loans to be fully charged-off	120 days
Unsecured consumer loans [Member]
Summary Of Significant Accounting Policies [Line Items]
Number of days past due of loans to be fully charged-off	150 days
Commercial and Industrial Loans [Member]
Summary Of Significant Accounting Policies [Line Items]
Loans evaluated for impairment	250,000
Old Harbor Bank [Member] | First United Bancorp, Inc. [Member]
Summary Of Significant Accounting Policies [Line Items]
FDIC loss share coverage percentage up to first tranche					70.00%
FDIC loss share recovery limit first tranche					49,000,000
The Bank Of Miami [Member] | First United Bancorp, Inc. [Member]
Summary Of Significant Accounting Policies [Line Items]
FDIC loss share coverage percentage up to first tranche					80.00%
Republic Federal Bank [Member] | First United Bancorp, Inc. [Member]
Summary Of Significant Accounting Policies [Line Items]
FDIC loss share coverage percentage up to first tranche					80.00%
FDIC loss share recovery limit first tranche					$ 36,000,000
FDIC loss share coverage percentage up to first tranche					95.00%