Stock Repurchase Program - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	May 31, 2020	May 31, 2019	May 31, 2018	May 31, 2021
Stock Repurchase Programs [Line Items]
Authorization of stock repurchase program		Jan. 08, 2008
Shares repurchased	2,041,847	3,286,907	0
Shares repurchased, value	$ 125,000	$ 200,222
Repurchase of common stock price per shares	$ 61.22	$ 60.92
Scenario Forecast
Stock Repurchase Programs [Line Items]
Capital to be returned to stockholders through share repurchases				$ 1,000,000
Stock repurchase program, remaining authorized repurchase, value				$ 600,000