Subordinated Debentures - Additional Information (Details) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2003	Mar. 31, 2013	Sep. 30, 2012	Dec. 31, 2008
Subordinated Debentures [Abstract]
Holding Company, closed a pooled private offering		5,000
Trust preferred securities with a liquidation amount		$ 1
Subordinated debentures	$ 5,155	$ 5,155	$ 5,155
Holding Company's investment in the common stock		155
Holding Company may redeem the subordinated debentures in a principal amount with integral multiples					$ 1
Percentage in which holding company redeem subordinated debentures					100.00%
Maturity date of subordinated debentures	Dec. 30, 2033
Cumulative deferred interest payments	$ 42		$ 83	$ 348
Trust preferred securities and subordinated debentures have a variable rate of interest			2.85%
Trust preferred securities and subordinated debentures have a stated percentage	3.21%		3.16%