Investments In Affordable Housing (Details) (USD $)	9 Months Ended	12 Months Ended
	Sep. 30, 2011	Dec. 31, 2010
Schedule of Investments [Line Items]
Increase in total assets and liabilities from consolidating affordable housing equity interest	$ 22,900,000	$ 22,800,000
Investments in affordable housing partnerships	80,592,000	88,472,000
Number of equity interest limited partnerships in affordable housing investments	6	6
Affordable Housing Limited Partnerships [Member]
Schedule of Investments [Line Items]
Other borrowings for affordable housing limited partnerships	19,000,000	19,100,000
Unfunded commitment liabilities for affordable housing investments	$ 1,500,000	$ 4,300,000