Commercial Mortgage Residual Interests (Schedule Of Amounts Recognized As Unrealized Gains And/Or Losses Recorded As Other Comprehensive Income And Other Than Temporary Valuation Impairments Recorded In Earnings) (Details) (USD $) In Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Commercial Mortgage Residual Interests [Abstract]
Unrealized gains		$ 658	$ 599	$ 785
Other than temporary valuation impairment			$ 396	$ 3,848