Commitments, Guarantees, And Contingent Liabilities (Schedule Of Guarantees Issued) (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Liabilities for Guarantees on Long-Duration Contracts [Line Items]
Unused Commitments to Extend Credit	$ 17,310,427	$ 17,169,785
Commercial Letters Of Credit	58,567	18,447
Total Unfunded Lending Commitments	18,216,165	18,066,629
Financial [Member]
Liabilities for Guarantees on Long-Duration Contracts [Line Items]
Standby letters of credit	643,514	661,554
Performance [Member]
Liabilities for Guarantees on Long-Duration Contracts [Line Items]
Standby letters of credit	$ 203,657	$ 216,843