Schedule Of Unallocated Items and Eliminations (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Segment Reporting Information [Line Items]
Share-based plans			$ (151)	$ (144)
Earnings from operations	$ 2,689	$ 2,282	7,248	3,651
Pension Plans, Defined Benefit [Member]
Segment Reporting Information [Line Items]
Pension and Postretirement Expense	(100)	(453)	(534)	(1,545)
Other Postretirement Benefit Plan, Defined Benefit [Member]
Segment Reporting Information [Line Items]
Pension and Postretirement Expense	(58)	(63)	(201)	(213)
Unallocated items, eliminations and other [Member]
Segment Reporting Information [Line Items]
Share-based plans	(21)	(9)	(67)	(50)
Deferred compensation	(78)	(33)	(174)	(38)
Amortization of previously capitalized interest	(21)	(23)	(72)	(71)
Eliminations and other unallocated items	(78)	(135)	(437)	(333)
Sub-total	(198)	(200)	(750)	(492)
Pension and Postretirement Expense	316	88	954	251
Earnings from operations	118	(112)	204	(241)
Unallocated items, eliminations and other [Member] | Pension Plans, Defined Benefit [Member]
Segment Reporting Information [Line Items]
Pension and Postretirement Expense	275	50	808	129
Unallocated items, eliminations and other [Member] | Other Postretirement Benefit Plan, Defined Benefit [Member]
Segment Reporting Information [Line Items]
Pension and Postretirement Expense	$ 41	$ 38	$ 146	$ 122