Accumulated Other Comprehensive Income (Loss) (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Foreign exchange gains (losses)	$ (6.9)	$ 16.3	$ (23.7)