Shareholders' Equity (Reclassifications Out of Accumulated Other Comprehensive Income by Component) (Details) - USD ($) $ in Millions		3 Months Ended												12 Months Ended
		Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017		Sep. 30, 2017		Jun. 30, 2017		Mar. 31, 2017		Dec. 31, 2018	Dec. 31, 2017		Dec. 31, 2016
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Sales		$ 3,035	$ 3,008	$ 2,747	$ 2,500	$ 2,637		$ 2,607		$ 2,497		$ 2,375		$ 11,290	$ 10,116		$ 9,390
Cost of sales														6,829	6,096		5,627
Other income (expense), net														(216)	(81)		(117)
Tax benefit (expense)		$ 54	$ 133	$ 126	$ 124	$ 1,978	[1]	$ 89	[1]	$ 153	[1]	$ (66)	[1]	437	2,154	[1]	(3)
Total reclassifications for the period	[2],[3]													(93)	(42)	[4]	(62)	[4]
Accumulated Defined Benefit Plans Adjustment, Net Prior Service Attributable to Parent [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax	[3],[5]													(138)	(20)		(62)
Accumulated Defined Benefit Plans Adjustment, Net Gain (Loss) Attributable to Parent [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax	[3],[5]													(6)	(2)		(1)
Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax	[3]													(144)	(22)		(63)
Reclassification from AOCI, Current Period, Tax	[3]													41	5		23
Total reclassifications for the period	[2],[3]													(103)	(17)	[4]	(40)	[4]
Accumulated Net Investment Gain (Loss) Attributable to Parent [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total reclassifications for the period	[2],[4]														(14)
Accumulated Net Investment Gain (Loss) Attributable to Parent [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other income (expense), net	[3]														(3)
Tax benefit (expense)	[3]														(11)
Net of tax	[3]														(14)
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total reclassifications for the period	[2]													10	(11)	[4]	(22)	[4]
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Sales	[3]														1		4
Cost of sales	[3]													13	(12)		(36)
Other income (expense), net	[3]													(1)	(2)		(2)
Total before tax	[3]													12	(13)		(34)
Tax benefit (expense)	[3]													(2)	2		12
Net of tax	[3]													$ 10	$ (11)		$ (22)

[1] In December 2017, the U.S. enacted the 2017 Tax Act which resulted in significant changes to our provision for income taxes during the fourth quarter of 2017. Refer to Note 4 (Income Taxes) to the Consolidated Financial Statements for additional information.

[2] All amounts are after tax. Amounts in parentheses indicate debits to accumulated other comprehensive income.

[3] Amounts in parentheses indicate debits to the statement of income.

[4] Tax effects of reclassifications are disclosed separately in this Note 15.

[5] These accumulated other comprehensive income components are included in net periodic pension cost. See Note 11 (Employee Retirement Plans) to the Consolidated Financial Statements for additional details.