Earnings Per Share - Computation of Basic Earnings Per Share, Assuming Dilution (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended						9 Months Ended
	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Sep. 30, 2019	Sep. 30, 2018
Numerator:
Net Earnings	$ 856	$ 870	$ 834	$ 894	$ 877	$ 695	$ 2,560	$ 2,466
Denominator:
Average Common Shares Outstanding (in shares)	790			850			803	866
Other Potentially Dilutive Common Shares (in shares)	2			4			2	4
Average Common Shares Outstanding, Assuming Dilution (in shares)	792			854			805	870
Net Earnings Per Share, Basic (in dollars per share)	$ 1.08			$ 1.05			$ 3.19	$ 2.85
Net Earnings Per Share, Assuming Dilution (in dollars per share)	$ 1.08			$ 1.05			$ 3.18	$ 2.83