Deposits (Schedule Of Certificates Of Deposit $100 Thousand Or More) (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
U.S. certificates of deposits:
Three months or less	$ 1,414.6	$ 1,725.4
After three months through six months	1,519.0	1,902.6
After six months through twelve months	2,825.3	2,907.7
After twelve months	5,713.4	7,013.4
Total	$ 11,472.3	$ 13,549.1