Derivative Instruments and Hedging Activities (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Foreign Exchange Contract [Member]
Derivative instrument, terms	The terms of our forward foreign exchange contracts are generally less than 90 days.
Foreign Exchange Contract [Member] | Fair Value Hedge [Member] | Designated as Hedging Instrument [Member]
Derivative instrument, fair value, net	$ 0.9	$ (1.1)
Foreign Exchange Contract [Member] | Foreign Exchange Risk of Intercompany Borrowing and Investment Activities [Member] | Fair Value Hedge [Member] | Designated as Hedging Instrument [Member]
Derivative instrument, notional amount	92.8	99.0
Foreign Exchange Contract [Member] | Foreign Exchange Risk of Revenue and Expenses Denominated in Different Currencies [Member] | Fair Value Hedge [Member] | Designated as Hedging Instrument [Member]
Derivative instrument, notional amount	136.3	94.0
Interest Rate Swap [Member]
Derivative instrument, notional amount	$ 1,250.0	$ 1,250.0