Accumulated Other Comprehensive Income (Loss) (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Foreign exchange gains (losses)	$ 0.8	$ (6.9)	$ 16.3