Derivative Financial Instruments (Schedule Of Notional Amounts Of Outstanding Derivative Positions) (Details) - Mar. 31, 2018 € in Millions, ¥ in Millions, £ in Millions, kr in Millions, R$ in Millions, $ in Millions, $ in Millions, $ in Millions, $ in Millions	EUR (€)	USD ($)	CAD ($)	BRL (R$)	NOK (kr)	SGD ($)	GBP (£)	JPY (¥)	AUD ($)
Foreign Exchange Forward | Australian dollar | Notional Amount Bought
Derivative
Derivative, notional amount		$ 204.8							$ 265.0
Foreign Exchange Forward | Brazilian real | Notional Amount Bought
Derivative
Derivative, notional amount		204.3		R$ 679.0
Foreign Exchange Forward | British pound | Notional Amount Bought
Derivative
Derivative, notional amount		315.0					£ 222.7
Foreign Exchange Forward | Canadian dollar | Notional Amount Sold
Derivative
Derivative, notional amount		136.0	$ 175.4
Foreign Exchange Forward | Euro | Notional Amount Bought
Derivative
Derivative, notional amount	€ 326.4	402.9
Foreign Exchange Forward | Mexican peso | Notional Amount Sold
Derivative
Derivative, notional amount	€ 203.0	11.0
Foreign Exchange Forward | Norwegian krone | Notional Amount Sold
Derivative
Derivative, notional amount		373.4			kr 2,928.1
Foreign Exchange Forward | Singapore dollar | Notional Amount Bought
Derivative
Derivative, notional amount		49.7				$ 65.0
Foreign Exchange Forward | Japanese yen | Notional Amount Bought
Derivative
Derivative, notional amount		18.5						¥ 1,940.8
Foreign Exchange Forward | U.S. dollar | Notional Amount Sold
Derivative
Derivative, notional amount		19.1
Derivative financial instruments – Embedded Derivatives | Brazilian real | Notional Amount Sold
Derivative
Derivative, notional amount		11.3		R$ 37.7
Derivative financial instruments – Embedded Derivatives | Norwegian krone | Notional Amount Sold
Derivative
Derivative, notional amount		14.2			kr 111.2
Derivative financial instruments – Embedded Derivatives | U.S. dollar | Notional Amount Bought
Derivative
Derivative, notional amount		$ 17.5