Long-Term Debt And Borrowing Arrangements (Schedule Of Committed Credit Facilities) (Detail) (USD $) In Millions, unless otherwise specified	Sep. 30, 2012
Revolving Credit Facility Maturing 2016 [Member]
Line of Credit Facility [Line Items]
Total Capacity	$ 1,435
Outstanding Borrowings	0
Letters of Credit Issued	1,155
Available Capacity	280
Other Facilities [Member]
Line of Credit Facility [Line Items]
Total Capacity	10
Outstanding Borrowings	3
Available Capacity	$ 7