Income Taxes - Schedule of Significant Components of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Millions	May 31, 2022	May 31, 2021
Components of Deferred Tax Assets and Liabilities [Abstract]
Property, equipment, leases and intangibles	$ 4,464	$ 4,248
Employee benefits	1,203	1,178
Self-insurance accruals	931	785
Other	524	511
Net operating loss/credit carryforwards	1,079	934
Valuation allowances	(413)	(382)
Deferred Tax Assets, Net	7,788	7,274
Property, equipment, leases and intangibles	10,608	9,731
Other	66	52
Deferred Tax Liabilities	$ 10,674	$ 9,783