Employee Benefit Plans (Assets Held In Trust) (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Defined Benefit Plan Disclosure [Line Items]
Assets held-in-trust	$ 37.1	$ 35.2
Corporate-Owned Life Insurance Policies [Member]
Defined Benefit Plan Disclosure [Line Items]
Assets held-in-trust	36.0	34.9
Cash and Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Assets held-in-trust	$ 1.1	$ 0.3