Pension & Postretirement 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, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Pension And Postretirement Plan Expenses [Line Items]
Service cost	$ 24	$ 26	$ 71	$ 79
Interest cost	62	56	184	169
Expected return on plan assets	(86)	(83)	(258)	(249)
Net amortization	37	58	110	174
Total	$ 37	$ 57	$ 107	$ 173