Earnings Per Share - Computation of Basic Earnings Per Share, Assuming Dilution (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Numerator:
Net Earnings	$ 695	$ 362
Denominator:
Average Common Shares Outstanding (in shares)	885	927
Other Potentially Dilutive Common Shares (in shares)	3	2
Average Common Shares Outstanding, Assuming Dilution (in shares)	888	929
Net Earnings Per Share, Basic (in dollars per share)	$ 0.78	$ 0.39
Net Earnings Per Share, Assuming Dilution (in dollars per share)	$ 0.78	$ 0.39