Investment Securities (Details 4) (USD $)	Sep. 30, 2011	Dec. 31, 2010
Schedule of Available-for-sale Securities [Line Items]
Unrealized loss position on other securities	$ (3,205,000)	$ (45,824,000)
Investment Securities (Textuals) [Abstract]
Federal Home Loan Bank Stock	121,100,000
Federal Reserve Bank Stock	70,000,000	69,900,000
Obligations of state and political subdivisions [Member]
Schedule of Available-for-sale Securities [Line Items]
Number of investment securities in an unrealized position less than Twelve months	3
Number of investment securities in an unrealized position for Twelve months or more	1
Unrealized loss position on other securities	(38,000)	(5,350,000)
Residential mortgage-related securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Number of investment securities in an unrealized position less than Twelve months	40
Number of investment securities in an unrealized position for Twelve months or more	10
Unrealized loss position on other securities	(1,213,000)	(38,514,000)
Asset-backed securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Number of investment securities in an unrealized position less than Twelve months	14
Number of investment securities in an unrealized position for Twelve months or more	18
Unrealized loss position on other securities	(723,000)	(621,000)
Trust Preferred Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Number of individual trust preferred debt securities	3
Unrealized loss position on other securities	$ 1,200,000
Floating rate notes [Member]
Schedule of Available-for-sale Securities [Line Items]
Number of investment securities in an unrealized position for Twelve months or more	6