Fair Value Measurements - Assets and Liabilities Measured at Fair Value on a Recurring Basis (Detail) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Total investment securities available-for-sale	$ 308,359	$ 331,128
US Government-Sponsored Enterprises (GSEs) [Member]
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Total investment securities available-for-sale	53,572	76,909
State and Municipal Securities [Member]
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Total investment securities available-for-sale	32,615	31,270
Fair Value Measurements Recurring [Member]
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Total investment securities available-for-sale	308,359	331,128
Loans held for sale	6,236	10,135
Other assets	27,006	26,672
Total assets at fair value	341,601	367,935
Fair Value Measurements Recurring [Member] | Quoted Market Prices in an Active Market (Level 1) [Member]
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Total investment securities available-for-sale	0	0
Loans held for sale	0	0
Other assets	0	0
Total assets at fair value	0	0
Fair Value Measurements Recurring [Member] | Models with Significant Observable Market Parameters (Level 2) [Member]
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Total investment securities available-for-sale	308,359	331,128
Loans held for sale	6,236	10,135
Other assets	0	0
Total assets at fair value	314,595	341,263
Fair Value Measurements Recurring [Member] | Models with Significant Unobservable Market Parameters (Level 3) [Member]
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Total investment securities available-for-sale	0	0
Loans held for sale	0	0
Other assets	27,006	26,672
Total assets at fair value	27,006	26,672
Fair Value Measurements Recurring [Member] | US Government-Sponsored Enterprises (GSEs) [Member]
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Total investment securities available-for-sale	53,572	76,909
Fair Value Measurements Recurring [Member] | US Government-Sponsored Enterprises (GSEs) [Member] | Quoted Market Prices in an Active Market (Level 1) [Member]
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Total investment securities available-for-sale	0	0
Fair Value Measurements Recurring [Member] | US Government-Sponsored Enterprises (GSEs) [Member] | Models with Significant Observable Market Parameters (Level 2) [Member]
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Total investment securities available-for-sale	53,572	76,909
Fair Value Measurements Recurring [Member] | US Government-Sponsored Enterprises (GSEs) [Member] | Models with Significant Unobservable Market Parameters (Level 3) [Member]
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Total investment securities available-for-sale	0	0
Fair Value Measurements Recurring [Member] | Mortgage Backed Securities [Member]
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Total investment securities available-for-sale	192,358	191,915
Fair Value Measurements Recurring [Member] | Mortgage Backed Securities [Member] | Quoted Market Prices in an Active Market (Level 1) [Member]
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Total investment securities available-for-sale	0	0
Fair Value Measurements Recurring [Member] | Mortgage Backed Securities [Member] | Models with Significant Observable Market Parameters (Level 2) [Member]
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Total investment securities available-for-sale	192,358	191,915
Fair Value Measurements Recurring [Member] | Mortgage Backed Securities [Member] | Models with Significant Unobservable Market Parameters (Level 3) [Member]
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Total investment securities available-for-sale	0	0
Fair Value Measurements Recurring [Member] | Asset-backed Securities [Member]
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Total investment securities available-for-sale	29,814	31,034
Fair Value Measurements Recurring [Member] | Asset-backed Securities [Member] | Quoted Market Prices in an Active Market (Level 1) [Member]
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Total investment securities available-for-sale	0	0
Fair Value Measurements Recurring [Member] | Asset-backed Securities [Member] | Models with Significant Observable Market Parameters (Level 2) [Member]
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Total investment securities available-for-sale	29,814	31,034
Fair Value Measurements Recurring [Member] | Asset-backed Securities [Member] | Models with Significant Unobservable Market Parameters (Level 3) [Member]
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Total investment securities available-for-sale	0	0
Fair Value Measurements Recurring [Member] | State and Municipal Securities [Member]
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Total investment securities available-for-sale	32,615	31,270
Fair Value Measurements Recurring [Member] | State and Municipal Securities [Member] | Quoted Market Prices in an Active Market (Level 1) [Member]
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Total investment securities available-for-sale	0	0
Fair Value Measurements Recurring [Member] | State and Municipal Securities [Member] | Models with Significant Observable Market Parameters (Level 2) [Member]
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Total investment securities available-for-sale	32,615	31,270
Fair Value Measurements Recurring [Member] | State and Municipal Securities [Member] | Models with Significant Unobservable Market Parameters (Level 3) [Member]
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Total investment securities available-for-sale	$ 0	$ 0