Earnings (Loss) Per Common Share - Basic and Diluted Earning Per Share (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Disclosure Earning Per Share Additional Information [Abstract]
Weighted average shares outstanding used in Basic Earnings per Common Share									7,939,433	7,880,249	7,511,173
Dilutive effect of stock options									4,485	0	0
Weighted average shares outstanding used in Diluted Earnings Per Common Share									7,943,918	7,880,249	7,511,173
Net income	$ 1,639	$ 1,525	$ 1,438	$ 1,505	$ 1,489	$ 1,672	$ 712	$ 1,130	$ 6,107	$ 5,003	$ 5,365
Preferred stock dividend and accretion									1,266	1,276	1,276
Income Available to Common Shareholders									$ 4,841	$ 3,727	$ 4,089
Basic Earnings Per Common Share	$ 0.17	$ 0.15	$ 0.14	$ 0.15	$ 0.15	$ 0.17	$ 0.05	$ 0.10	$ 0.61	$ 0.47	$ 0.55
Diluted Earnings Per Common Share	$ 0.17	$ 0.15	$ 0.14	$ 0.15	$ 0.15	$ 0.17	$ 0.05	$ 0.10	$ 0.61	$ 0.47	$ 0.55