Credit Losses - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Nov. 30, 2021	Nov. 30, 2020	Nov. 30, 2021	Nov. 30, 2020	May 31, 2021
Credit Loss [Abstract]
Credit losses	$ 94	$ 148	$ 211	$ 291
Allowance for credit losses	$ 362		$ 362		$ 358