Loans and Allowance for Loan and Lease Losses - Summary of Delinquency Status of Loans by Portfolio Type (Detail) $ in Thousands	Jun. 30, 2016 USD ($)	Dec. 31, 2015 USD ($) Loan
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	$ 19,820	$ 20,257
Current	864,607	841,461
Total loans	884,427	861,718
Loans greater than 90 Days and Accruing	0	$ 0
Number of mortgage loans in process of foreclosure | Loan		1
Mortgage loans in process of foreclosure, amount		$ 535
Commercial loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	10,125	11,784
Current	332,454	335,516
Total loans	342,579	347,300
Loans greater than 90 Days and Accruing	0	0
Consumer loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	115	0
Current	38,519	28,663
Total loans	38,634	28,663
Loans greater than 90 Days and Accruing	0	0
Commercial real estate | Owner occupied
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	1,016	797
Current	215,829	194,757
Total loans	216,845	195,554
Loans greater than 90 Days and Accruing	0	0
Commercial real estate | All other
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	5,060	5,523
Current	136,823	141,118
Total loans	141,883	146,641
Loans greater than 90 Days and Accruing	0	0
Residential mortgage loans | Multi-family
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	2,364	0
Current	89,737	81,487
Total loans	92,101	81,487
Loans greater than 90 Days and Accruing	0	0
Residential mortgage loans | Single family
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	0	535
Current	39,823	51,537
Total loans	39,823	52,072
Loans greater than 90 Days and Accruing	0	0
Land development loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	1,140	1,618
Current	11,422	8,383
Total loans	12,562	10,001
Loans greater than 90 Days and Accruing	0	0
30-59 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	5,624	2,326
30-59 Days Past Due | Commercial loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	3,145	2,010
30-59 Days Past Due | Consumer loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	115	0
30-59 Days Past Due | Commercial real estate | Owner occupied
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	0	0
30-59 Days Past Due | Commercial real estate | All other
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	0	316
30-59 Days Past Due | Residential mortgage loans | Multi-family
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	2,364	0
30-59 Days Past Due | Residential mortgage loans | Single family
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	0	0
30-59 Days Past Due | Land development loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	0	0
60-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	70	1,008
60-89 Days Past Due | Commercial loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	70	1,008
60-89 Days Past Due | Consumer loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	0	0
60-89 Days Past Due | Commercial real estate | Owner occupied
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	0	0
60-89 Days Past Due | Commercial real estate | All other
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	0	0
60-89 Days Past Due | Residential mortgage loans | Multi-family
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	0	0
60-89 Days Past Due | Residential mortgage loans | Single family
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	0	0
60-89 Days Past Due | Land development loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	0	0
90 Days and Greater
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	14,126	16,923
90 Days and Greater | Commercial loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	6,910	8,766
90 Days and Greater | Consumer loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	0	0
90 Days and Greater | Commercial real estate | Owner occupied
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	1,016	797
90 Days and Greater | Commercial real estate | All other
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	5,060	5,207
90 Days and Greater | Residential mortgage loans | Multi-family
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	0	0
90 Days and Greater | Residential mortgage loans | Single family
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	0	535
90 Days and Greater | Land development loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	$ 1,140	$ 1,618