Derivative Financial Instruments (Schedule Of Notional Amounts Of Outstanding Derivative Positions) (Details) - Sep. 30, 2017 € in Millions, ¥ in Millions, £ in Millions, SGD in Millions, NOK in Millions, MYR in Millions, CAD in Millions, BRL in Millions, AUD in Millions, $ in Millions	USD ($)	EUR (€)	GBP (£)	CAD	BRL	MYR	SGD	NOK	JPY (¥)	AUD
Foreign Exchange Forward | Australian dollar | Notional Amount Bought
Derivative
Derivative, notional amount	$ 233.6									AUD 293.9
Foreign Exchange Forward | Brazilian real | Notional Amount Bought
Derivative
Derivative, notional amount	238.6				BRL 755.6
Foreign Exchange Forward | British pound | Notional Amount Bought
Derivative
Derivative, notional amount	315.7		£ 233.9
Foreign Exchange Forward | Canadian dollar | Notional Amount Sold
Derivative
Derivative, notional amount	151.2			CAD 188.4
Foreign Exchange Forward | Euro | Notional Amount Bought
Derivative
Derivative, notional amount	761.2	€ 641.7
Foreign Exchange Forward | Japanese yen | Notional Amount Sold
Derivative
Derivative, notional amount	13.4								¥ 1,507.6
Foreign Exchange Forward | Malaysian ringgit | Notional Amount Bought
Derivative
Derivative, notional amount	61.8					MYR 259.5
Foreign Exchange Forward | Norwegian krone | Notional Amount Sold
Derivative
Derivative, notional amount	196.9							NOK 1,567.2
Foreign Exchange Forward | Singapore dollar | Notional Amount Bought
Derivative
Derivative, notional amount	48.0						SGD 65.0
Foreign Exchange Forward | U.S. dollar | Notional Amount Sold
Derivative
Derivative, notional amount	1,259.1
Derivative financial instruments – Embedded Derivatives | Norwegian krone | Notional Amount Sold
Derivative
Derivative, notional amount	42.7							NOK 339.5
Derivative financial instruments – Embedded Derivatives | U.S. dollar | Notional Amount Bought
Derivative
Derivative, notional amount	$ 49.2