Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	May 31, 2021	May 31, 2020
Statement of Financial Position [Abstract]
Allowance on accounts receivable	$ 12,097	$ 35,433
Preferred stock, shares authorized (in shares)	100,000	100,000
Preferred stock, shares outstanding ( in shares)	0	0
Common stock, shares authorized (in shares)	425,000,000	425,000,000
Common stock, shares issued (in shares)	189,071,185	186,793,207
Common stock, shares outstanding (in shares)	104,061,391	103,415,368
Treasury stock, shares (in shares)	85,009,794	83,377,839