Concentrations of Credit Risk (Details) (Commercial Real Estate [Member], USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Concentration Risk [Line Items]
Concentration of credit risk, loan portfolio, maximum exposure	$ 304,308	$ 303,192
College Housing and Professional Office Buildings [Member]
Concentration Risk [Line Items]
Concentration of credit risk, loan portfolio, maximum exposure	171,186	166,710
Residential [Member]
Concentration Risk [Line Items]
Concentration of credit risk, loan portfolio, maximum exposure	143,262	150,224
Automobile [Member]
Concentration Risk [Line Items]
Concentration of credit risk, loan portfolio, maximum exposure	$ 11,764	$ 13,089
Credit Concentration Risk [Member]
Concentration Risk [Line Items]
Concentration of credit risk, percentage (in hundredths)	51.00%
Credit Concentration Risk [Member] | College Housing and Professional Office Buildings [Member]
Concentration Risk [Line Items]
Concentration of credit risk, percentage (in hundredths)	29.00%	28.00%
Credit Concentration Risk [Member] | Residential [Member]
Concentration Risk [Line Items]
Concentration of credit risk, percentage (in hundredths)	24.00%	26.00%
Credit Concentration Risk [Member] | Automobile [Member]
Concentration Risk [Line Items]
Concentration of credit risk, percentage (in hundredths)	2.00%	2.00%