Retirement Plans - Schedule of Change in Fair Value of Level 3 Assets (Details) - Pension Plans [Member] - USD ($) $ in Millions	12 Months Ended
	May 31, 2022	May 31, 2021
Defined Benefit Plan Disclosure [Line Items]
Balance at beginning of year	$ 31,918
Actual return on plan assets:
Balance at end of year	26,633	$ 31,918
U.S. Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Balance at beginning of year	29,785	26,978
Actual return on plan assets:
Balance at end of year	25,970	29,785
Fair Value Inputs Level 3 [Member] | U.S. Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Balance at beginning of year	537	416
Actual return on plan assets:
Assets held during current year	192	41
Assets sold during the year	29	22
Purchases, sales and settlements	53	58
Balance at end of year	$ 811	$ 537