Allowance for Loan Losses - Risk Category of Loans by Class of Loans (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Accounts Notes And Loans Receivable [Line Items]
Total loans	$ 1,536,500	$ 1,166,426
Residential Properties
Accounts Notes And Loans Receivable [Line Items]
Total loans	999,720	842,135
Commercial Real Estate
Accounts Notes And Loans Receivable [Line Items]
Total loans	329,972	205,320
Commercial and Industrial Loans
Accounts Notes And Loans Receivable [Line Items]
Total loans	158,259	93,537
Consumer Loans
Accounts Notes And Loans Receivable [Line Items]
Total loans	35,979	21,125
Land and Construction
Accounts Notes And Loans Receivable [Line Items]
Total loans	12,570	4,309
Pass
Accounts Notes And Loans Receivable [Line Items]
Total loans	1,512,534	1,145,988
Pass | Residential Properties
Accounts Notes And Loans Receivable [Line Items]
Total loans	998,220	841,538
Pass | Commercial Real Estate
Accounts Notes And Loans Receivable [Line Items]
Total loans	323,248	198,112
Pass | Commercial and Industrial Loans
Accounts Notes And Loans Receivable [Line Items]
Total loans	143,747	81,067
Pass | Consumer Loans
Accounts Notes And Loans Receivable [Line Items]
Total loans	35,890	20,962
Pass | Land and Construction
Accounts Notes And Loans Receivable [Line Items]
Total loans	11,429	4,309
Special Mention
Accounts Notes And Loans Receivable [Line Items]
Total loans	3,101	7,096
Special Mention | Residential Properties
Accounts Notes And Loans Receivable [Line Items]
Total loans	1,500	554
Special Mention | Commercial Real Estate
Accounts Notes And Loans Receivable [Line Items]
Total loans		1,266
Special Mention | Commercial and Industrial Loans
Accounts Notes And Loans Receivable [Line Items]
Total loans	1,601	5,276
Substandard
Accounts Notes And Loans Receivable [Line Items]
Total loans	6,662	1,806
Substandard | Commercial Real Estate
Accounts Notes And Loans Receivable [Line Items]
Total loans	358	200
Substandard | Commercial and Industrial Loans
Accounts Notes And Loans Receivable [Line Items]
Total loans	5,163	1,559
Substandard | Consumer Loans
Accounts Notes And Loans Receivable [Line Items]
Total loans		47
Substandard | Land and Construction
Accounts Notes And Loans Receivable [Line Items]
Total loans	1,141
Impaired
Accounts Notes And Loans Receivable [Line Items]
Total loans	14,203	11,536
Impaired | Residential Properties
Accounts Notes And Loans Receivable [Line Items]
Total loans		43
Impaired | Commercial Real Estate
Accounts Notes And Loans Receivable [Line Items]
Total loans	6,366	5,742
Impaired | Commercial and Industrial Loans
Accounts Notes And Loans Receivable [Line Items]
Total loans	7,748	5,635
Impaired | Consumer Loans
Accounts Notes And Loans Receivable [Line Items]
Total loans	$ 89	$ 116