Junior Subordinated Debentures (Narrative) (Details) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011	Dec. 31, 2011	Dec. 31, 2009 Dodd-Frank Act [Member]
Junior Subordinated Debentures [Line Items]
Common stock issued by trust owned	$ 6,900,000		$ 6,900,000		$ 6,900,000
Loss on junior subordinated debentures carried at fair value	(547,000)	(547,000)	(1,095,000)	(1,089,000)
Assets	$ 11,521,897,000		$ 11,521,897,000		$ 11,563,355,000	$ 15,000,000,000
Restricted core capital percentage	18.00%		18.00%