Securities Available-for Sale - Schedule of Security with Unrealized Losses (Detail) (U.S. Government-Sponsored Entities [Member], USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
U.S. Government-Sponsored Entities [Member]
Schedule of Available-for-sale Securities [Line Items]
Less Than 12 Month, Fair Value	$ 999	$ 3,985
Less Than 12 Month, Unrealized Loss	(1)	(15)
12 Months or More, Fair Value	992	981
12 Months or More, Unrealized Loss	(8)	(19)
Total, Fair Value	1,991	4,966
Total, Unrealized Loss	$ (9)	$ (34)