Commitments and Contingencies (Details) (USD $) In Thousands, unless otherwise specified									9 Months Ended
	Sep. 30, 2012 Commitments to extend credit	Dec. 31, 2011 Commitments to extend credit	Sep. 30, 2012 Undisbursed lines of credit	Dec. 31, 2011 Undisbursed lines of credit	Sep. 30, 2012 Undisbursed portions of construction loans	Dec. 31, 2011 Undisbursed portions of construction loans	Sep. 30, 2012 Standby letters of credit and financial guarantees	Dec. 31, 2011 Standby letters of credit and financial guarantees	Sep. 30, 2012 Minimum Undisbursed lines of credit	Sep. 30, 2012 Maximum Undisbursed lines of credit	Sep. 30, 2012 Maximum Standby letters of credit and financial guarantees
Commitments and Contingencies
Commitments to extend credit	$ 142,504	$ 129,005	$ 141,914	$ 128,585	$ 3,180	$ 2,923	$ 590	$ 420
Commitments to extend credit, term of agreement									1 month	12 months	1 year