CONSOLIDATED INCOME STATEMENTS - USD ($) shares in Millions, $ in Millions	12 Months Ended
	Dec. 25, 2015	Dec. 26, 2014	Dec. 27, 2013
Income Statement [Abstract]
Revenue	$ 11,811	$ 12,669	$ 12,026
Expense
Labor and Fringe	3,290	3,377	3,138
Materials, Supplies and Other	2,336	2,484	2,275
Fuel	957	1,616	1,656
Depreciation	1,208	1,151	1,104
Equipment and Other Rents	436	428	380
Total Expense	8,227	9,056	8,553
Operating Income	3,584	3,613	3,473
Interest Expense	(544)	(545)	(562)
Other Income - Net	98	(24)	11
Earnings Before Income Taxes	3,138	3,044	2,922
Income Tax Expense	(1,170)	(1,117)	(1,058)
Net Earnings	$ 1,968	$ 1,927	$ 1,864
Net Earnings Per Share, Basic
Net Earnings Per Share, Basic (dollars per share)	$ 2.00	$ 1.93	$ 1.83
Net Earnings Per Common Share, Assuming Dilution
Net Earnings Per Share, Assuming Dilution (dollars per share)	$ 2.00	$ 1.92	$ 1.83
Average Common Shares Outstanding, Basic (shares)	983	1,001	1,019
Average Common Shares Outstanding, Assuming Dilution (shares)	984	1,002	1,019
Common Stock Dividends (dollars per share)	$ 0.70	$ 0.63	$ 0.59