Summary of Trade Accounts Receivable Net of Allowances and Net Contract Assets (Liabilities) (Detail) - USD ($) $ in Thousands	3 Months Ended
	Aug. 31, 2020	May 31, 2020
Disaggregation Of Revenue [Line Items]
Trade accounts receivable, less allowances	$ 1,159,130	$ 1,137,957
Contract assets	36,292	25,249
Contract liabilities - short-term	(25,605)	(25,288)
Net Contract Assets (Liabilities)	10,687	$ (39)
Change in Contract with Customer, Asset and Liability [Abstract]
Change in trade accounts receivable, less allowance	21,173
Change in contract assets	11,043
Change in Net Contract Assets (Liabilities)	$ 10,726
Percentage of change in trade accounts receivable, less allowance	1.90%
Percentage of change in contract assets	43.70%
Short-term
Change in Contract with Customer, Asset and Liability [Abstract]
Change in contract liabilities	$ (317)
Percentage of change in contract liabilities	1.30%