Schedule Of Unallocated Items and Eliminations (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Segment Reporting Information [Line Items]
Share-based plans	$ (51)	$ (50)
Earnings from operations	1,788	2,019
Pension Plans, Defined Benefit [Member]
Segment Reporting Information [Line Items]
Pension and Postretirement Expense	(629)	(785)
Other Postretirement Benefit Plans, Defined Benefit [Member]
Segment Reporting Information [Line Items]
Pension and Postretirement Expense	(88)	(92)
Unallocated items, eliminations and other [Member]
Segment Reporting Information [Line Items]
Share-based plans	(23)	(21)
Deferred compensation	16	(58)
Amortization of previously capitalized interest	(30)	(29)
Total Other and Eliminations	(129)	(140)
Sub-total	(166)	(248)
Pension and Postretirement Expense	94	(113)
Earnings from operations	(72)	(361)
Unallocated items, eliminations and other [Member] | Pension Plans, Defined Benefit [Member]
Segment Reporting Information [Line Items]
Pension and Postretirement Expense	45	(152)
Unallocated items, eliminations and other [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member]
Segment Reporting Information [Line Items]
Pension and Postretirement Expense	$ 49	$ 39