Stock-Based Compensation - Summary of Stock Option Activity (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
May 31, 2019	May 31, 2018	May 31, 2017
Stock Options
Outstanding, beginning of year	2,019	2,307	3,306
Granted	96	90	111
Exercised	(506)	(371)	(1,076)
Forfeited	(54)	(7)	(34)
Outstanding, end of year	1,555	2,019	2,307
Exercisable at end of year	1,397	1,800	2,067
Weighted Average Exercise Price
Outstanding, beginning of year	$ 22.26	$ 20.99	$ 19.01
Granted	42.86	47.76	42.30
Exercised	18.45	20.37	16.90
Forfeited	44.31	33.02	29.95
Outstanding, end of year	24.01	22.26	20.99
Exercisable at end of year	$ 21.96	$ 20.03	$ 19.17
Weighted Average Remaining Contractual Life (in years)
Outstanding	3 years 1 month 24 days	3 years 7 months 2 days	3 years 11 months 12 days
Exercisable	2 years 7 months 13 days	3 years 21 days	3 years 5 months 19 days
Aggregate intrinsic value
Outstanding	$ 18,728	$ 51,858	$ 48,509
Exercisable	$ 18,728	$ 50,673	$ 47,488

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.