Loss on Asset Disposal	6 Months Ended
	Jun. 30, 2020
Property, Plant and Equipment [Abstract]
Loss on Asset Disposal	Loss on Asset DisposalIn the first quarter of 2020, in connection with our initiatives to increase operational fluidity and asset utilization and improve labor and fuel efficiency, we committed to a plan to dispose of certain locomotives deemed excess and no longer needed for railroad operations. When depreciable operating road and equipment assets are sold or retired in the ordinary course of business, the cost of the assets, net of sale proceeds or salvage, is charged to accumulated depreciation, and no gain or loss is recognized in earnings. A retirement is considered abnormal if it does not occur in the ordinary course of business, if it relates to disposition of a large segment of an asset class and if the retirement varies significantly from the retirement profile identified through our depreciation studies, which inherently consider the impact of normal retirements on expected service lives and depreciation rates. We evaluated the planned locomotive retirements and concluded they were abnormal. Accordingly, a $385 million loss was recorded to adjust their carrying amount to their estimated fair value, which resulted in a $97 million tax benefit. During the first six months, we sold 446 of 703 locomotives under the plan. The carrying amount of the remaining assets held for sale of $29 million is classified as “Other current assets” in the Consolidated Balance Sheets at June 30, 2020.