Quarterly Financial Data - Unaudited (Tables)

12 Months Ended

Dec. 31, 2018

Quaterly Financial Data Unaudited [Abstract]

Schedule of Quarterly Financial Information

In millions

2019	Fourth		Third		Second		First
Revenues	$	5,839	$	6,021	$	5,893	$	5,762
Operating income	$	2,105	$	2,180	$	2,007	$	1,779
Net income	$	1,424	$	1,466	$	1,338	$	1,253

2018	Fourth		Third		Second		First
Revenues	$	6,206	$	6,147	$	5,878	$	5,624
Operating income	$	2,061	$	2,109	$	1,883	$	1,747
Net income	$	1,372	$	1,393	$	1,309	$	1,145