Pension And Postretirement Plan Expenses (Summary Of Net Periodic Pension And Net Postretirement Plan Expenses) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Pension And Postretirement Plan Expenses [Line Items]
Service cost	$ 26	$ 22	$ 79	$ 64
Interest cost	56	60	169	179
Expected return on plan assets	(83)	(80)	(249)	(239)
Net amortization	58	43	174	129
Total	$ 57	$ 45	$ 173	$ 133