Investment Securities (Realized gains and losses) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Investment Securities [Abstract]
Gross gains on sales of investment securities	$ 897	$ 1,316	$ 2,545	$ 3,189
Gross losses on sales of investment securities				69
Net gains on sales of investments	$ 897	$ 1,316	$ 2,545	$ 3,120