Stock-Based Compensation - Summary of Stock Option Activity (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
May 31, 2020	May 31, 2019	May 31, 2018
Stock Options
Outstanding, beginning of year	1,555	2,019	2,307
Granted	101	96	90
Exercised	(303)	(506)	(371)
Forfeited	(1)	(54)	(7)
Outstanding, end of year	1,352	1,555	2,019
Exercisable at end of year	1,167	1,397	1,800
Weighted Average Exercise Price
Outstanding, beginning of year	$ 24.01	$ 22.26	$ 20.99
Granted	38.91	42.86	47.76
Exercised	13.99	18.45	20.37
Forfeited	43.04	44.31	33.02
Outstanding, end of year	27.34	24.01	22.26
Exercisable at end of year	$ 25.34	$ 21.96	$ 20.03
Weighted Average Remaining Contractual Life (in years)
Outstanding	3 years 2 months 15 days	3 years 1 month 24 days	3 years 7 months 2 days
Exercisable	2 years 5 months 8 days	2 years 7 months 13 days	3 years 21 days
Aggregate intrinsic value
Outstanding	$ 8,846	$ 18,728	$ 51,858
Exercisable	$ 8,846	$ 18,728	$ 50,673

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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Period Type:	instant

- Definition

The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.