Derivative Instruments (Foreign Currency Contracts) (Details) - Mar. 31, 2019 - Foreign Exchange Forward - Not Designated as Hedging Instrument € in Millions, ¥ in Millions, £ in Millions, kr in Millions, $ in Millions, $ in Millions, $ in Millions, $ in Millions, $ in Millions	SGD ($)	HKD ($)	JPY (¥)	GBP (£)	EUR (€)	AUD ($)	DKK (kr)	USD ($)	CAD ($)
Long | Sell US Dollars and Buy Canadian Dollars
Derivative Instruments (Textual) [Abstract]
Amount of foreign currency contract									$ 24.4
Long | Sell Euros and Buy Canadian Dollars
Derivative Instruments (Textual) [Abstract]
Amount of foreign currency contract									$ 13.2
Long | Sell Australian Dollars and Buy Great Britain Pounds
Derivative Instruments (Textual) [Abstract]
Amount of foreign currency contract | £				£ 1.1
Long | Sell US Dollars and Buy Great Britain Pounds
Derivative Instruments (Textual) [Abstract]
Amount of foreign currency contract | £				33.1
Long | Sell US Dollars and Buy Singapore Dollars
Derivative Instruments (Textual) [Abstract]
Amount of foreign currency contract	$ 2.3
Long | Sell US Dollars and Buy Euros
Derivative Instruments (Textual) [Abstract]
Amount of foreign currency contract | €					€ 31.2
Long | Sell Japanese Yen and Buy US Dollars
Derivative Instruments (Textual) [Abstract]
Amount of foreign currency contract								$ 2.7
Long | Sell US Dollars And Buy Danish Krone
Derivative Instruments (Textual) [Abstract]
Amount of foreign currency contract | kr							kr 63.0
Long | Sell Euros and Buy Great British Pounds
Derivative Instruments (Textual) [Abstract]
Amount of foreign currency contract | £				7.3
Long | Sell Hong Kong Dollars and Buy Great British Pounds
Derivative Instruments (Textual) [Abstract]
Amount of foreign currency contract | £				£ 2.4
Short | Sell US Dollars and Buy Canadian Dollars
Derivative Instruments (Textual) [Abstract]
Amount of foreign currency contract								18.5
Short | Sell Euros and Buy Canadian Dollars
Derivative Instruments (Textual) [Abstract]
Amount of foreign currency contract | €					8.7
Short | Sell Australian Dollars and Buy Great Britain Pounds
Derivative Instruments (Textual) [Abstract]
Amount of foreign currency contract						$ 2.1
Short | Sell US Dollars and Buy Great Britain Pounds
Derivative Instruments (Textual) [Abstract]
Amount of foreign currency contract								43.2
Short | Sell US Dollars and Buy Singapore Dollars
Derivative Instruments (Textual) [Abstract]
Amount of foreign currency contract								1.7
Short | Sell US Dollars and Buy Euros
Derivative Instruments (Textual) [Abstract]
Amount of foreign currency contract								35.1
Short | Sell Japanese Yen and Buy US Dollars
Derivative Instruments (Textual) [Abstract]
Amount of foreign currency contract | ¥			¥ 300.0
Short | Sell US Dollars And Buy Danish Krone
Derivative Instruments (Textual) [Abstract]
Amount of foreign currency contract								$ 9.5
Short | Sell Euros and Buy Great British Pounds
Derivative Instruments (Textual) [Abstract]
Amount of foreign currency contract | €					€ 8.5
Short | Sell Hong Kong Dollars and Buy Great British Pounds
Derivative Instruments (Textual) [Abstract]
Amount of foreign currency contract		$ 24.6