Accounting Pronouncements ASU 2018-02 and ASU 2017-07 (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Early adoption of ASU 2018-02			26
Operating Expenses	$ 3,995	$ 3,476	$ 7,872	$ 7,081
Operating Income	1,883	1,774	3,630	3,354
Other (income) expense, net	$ (28)	(19)	$ (50)	$ (36)
Scenario, Previously Reported [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating Expenses		3,463
Operating Income		1,787
Other (income) expense, net		(6)
Restatement Adjustment [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating Expenses		13
Operating Income		(13)
Other (income) expense, net		$ (13)