Deposits (Schedule Of Rates And Maturities Of Deposits) (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Deposits, no stated maturity, Amount
Non-interest-bearing checking	$ 1,352.0
Interest-bearing checking	2,653.3
Money market	5,075.5
Savings	5,986.7
Other	153.7
Total checking and savings deposits	15,221.2
Certificates of deposit, remaining contractual maturity, Amount
Within one year	7,832.5
One to two years	3,069.7
Two to three years	1,619.8
Three to four years	633.2
Four to five years	167.1
Over five years	1,021.5
Total certificates of deposit	14,343.8
Purchase accounting adjustments	4.3
Total Deposits	$ 29,569.3	$ 32,304.3
Deposits — no stated maturity, Rate
Interest-bearing checking	0.59%
Money market	0.85%
Savings	1.12%
Certificates of deposit, remaining contractual maturity, Rate
Within one year	1.27%
One to two years	1.94%
Two to three years	2.23%
Three to four years	2.40%
Four to five years	2.35%
Over five years	3.32%
Total certificates of deposit	1.73%