Derivative Instruments and Hedging Activities - Gains and Losses (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2016
Derivative instruments and hedging activities
Impact on net income of unrealized gains and losses resulting from changes in fair value of derivative instruments	$ 4.4	$ (6.8)	$ 0.7
Foreign exchange contracts
Derivative instruments and hedging activities
Impact on net income of unrealized gains and losses resulting from changes in fair value of derivative instruments	3.0	(7.0)	5.8
Embedded derivative in purchase and delivery contracts
Derivative instruments and hedging activities
Impact on net income of unrealized gains and losses resulting from changes in fair value of derivative instruments		1.5	(5.7)
Fixed price commodity contracts
Derivative instruments and hedging activities
Impact on net income of unrealized gains and losses resulting from changes in fair value of derivative instruments	0.8	$ (1.3)	$ 0.6
Interest rate and cross currency swap agreements
Derivative instruments and hedging activities
Impact on net income of unrealized gains and losses resulting from changes in fair value of derivative instruments	$ 0.6