Securities - Amortized Cost and Fair Value of the Debt Securities Portfolio are Shown by Expected Maturity (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Available-for-sale Securities, Debt Maturities [Abstract]
Available-for-sale Securities, Debt Maturities, Next Twelve Months, Amortized Cost Basis	$ 21,419
Available-for-sale Securities, Debt Maturities, Year Two Through Five, Amortized Cost Basis	57,306
Available-for-sale Securities, Debt Maturities, Year Six Through Ten, Amortized Cost Basis	24,738
Available-for-sale Securities, Debt Maturities, after Ten Years, Amortized Cost Basis	5,593
Mortgage backed securities and collateralized mortgage obligations, Amortized cost	112,963
Amortized Cost	222,019	198,771
Available-for-sale Securities, Debt Maturities, Next Twelve Months, Fair Value	20,587
Available-for-sale Securities, Debt Maturities, Year Two Through Five, Fair Value	53,363
Available-for-sale Securities, Debt Maturities, Year Six Through Ten, Fair Value	23,583
Available-for-sale Securities, Debt Maturities, after Ten Years, Fair Value	5,504
Mortgage backed securities and collateralized mortgage obligations, Fair value	113,085
Fair Value	$ 216,122	$ 203,763