Fair Value of Financial Instruments (Assets Measured at Fair Value on a Nonrecurring Basis) (Details) (USD $)			3 Months Ended	9 Months Ended
	Sep. 30, 2012	Dec. 31, 2011	Sep. 30, 2012 Nonrecurring Basis	Sep. 30, 2012 Nonrecurring Basis	Sep. 30, 2012 Nonrecurring Basis Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans, aggregate outstanding principal balance	$ 24,619,000	$ 56,013,000			$ 6,200,000
Impaired loans, fair value					4,600,000
Losses on impaired loans charged through allowance for loan losses			200,000	1,600,000
Recorded losses for other real estate owned