Derivative Instruments And Hedging Activities (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2014
Disclosure Derivative Instruments And Hedging Activities Narrative [Abstract]
Derivative, Notional Amount	$ 0.8	$ 8.0
Net cash outflow/inflow from settlement of derivative contracts	0.0	0.0	$ (13.6)
Derivative Liability	$ 0.0	$ 0.1