Derivatives - Notional Amounts of Foreign Currency Forward Contracts (Details) - Foreign currency contracts - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Designated as hedges | Euro
Notional amounts of foreign currency forward contracts
Notional amounts	$ 388.1	$ 391.9
Designated as hedges | Canadian dollar
Notional amounts of foreign currency forward contracts
Notional amounts	98.3	99.0
Designated as hedges | British pound
Notional amounts of foreign currency forward contracts
Notional amounts	55.5	57.2
Designated as hedges | Australian dollar
Notional amounts of foreign currency forward contracts
Notional amounts	35.1	36.1
Designated as hedges | Swiss franc
Notional amounts of foreign currency forward contracts
Notional amounts	31.5
Designated as hedges | Japanese yen
Notional amounts of foreign currency forward contracts
Notional amounts		28.9
Designated as hedges | Other
Notional amounts of foreign currency forward contracts
Notional amounts	49.1	50.9
Not designated as hedges | Euro
Notional amounts of foreign currency forward contracts
Notional amounts	251.7	289.0
Not designated as hedges | Indian rupee
Notional amounts of foreign currency forward contracts
Notional amounts	82.6	52.3
Not designated as hedges | Canadian dollar
Notional amounts of foreign currency forward contracts
Notional amounts		78.1
Not designated as hedges | British pound
Notional amounts of foreign currency forward contracts
Notional amounts	59.1	110.3
Not designated as hedges | Mexican peso
Notional amounts of foreign currency forward contracts
Notional amounts	39.5	32.5
Not designated as hedges | Australian dollar
Notional amounts of foreign currency forward contracts
Notional amounts		61.0
Not designated as hedges | Brazilian real
Notional amounts of foreign currency forward contracts
Notional amounts	33.2	37.7
Not designated as hedges | Japanese yen
Notional amounts of foreign currency forward contracts
Notional amounts	26.5	35.2
Not designated as hedges | Other
Notional amounts of foreign currency forward contracts
Notional amounts	156.9	145.6
Maximum individual currency exposure within various other currencies	$ 25.0	$ 25.0