Fair Value Measurement (Details Textual) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Number of loans that were 90 days or more past due, or were any on nonaccrual status	0	0
Increase decrease in fair value of residential mortgage loans held for sale included in earnings	$ 0.8	$ 0.2
George Washington [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Estimated fair value of true up liability	4.3
George Washington Savings Bank [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Estimated fair value of true up liability	$ 7.2