Employee Benefits (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Retirement Benefits [Abstract]
Other compensation liabilities	$ 88.3	$ 91.7
Assets invested in defined contribution plans	88.8	91.8
Increase in deferred compensation liability	9.5	0.1	$ 9.0
Increase in defined contribution plan assets	9.9	0.2	9.0
Expenses in relation to qualified & non-qualified plans	$ 14.2	$ 14.4	$ 14.8