Income Taxes - Additional Information (Detail) - USD ($)	12 Months Ended
	May 31, 2021	May 31, 2020	May 31, 2019
Income Tax [Line Items]
Foreign capital loss carryforwards	$ 26,800,000
Total Valuation Allowances	64,696,000	$ 66,855,000
Unrecognized tax benefits that would impact effective tax rate, if recognized	7,000,000.0	8,600,000	$ 7,700,000
Accrued interest and penalties related to unrecognized tax benefits	2,900,000	2,900,000	$ 3,000,000.0
Unremitted foreign earnings	466,600,000
Deferred income tax liability	17,871,000	$ 8,781,000
Remaining unremitted foreign earnings	1,200,000,000
Provision for deferred income taxes	0
Capital Loss Carryforwards
Income Tax [Line Items]
Tax credit carryforwards	25,800,000
Tax credit carry forward amount subject to expiration	$ 21,500,000
Tax credit carryforwards expiration year	2022
State
Income Tax [Line Items]
Net operating loss carryforwards	$ 4,500,000
Net operating loss carryforwards beginning expiration year	2022
Foreign
Income Tax [Line Items]
Tax credit carryforwards	$ 27,300,000
Tax credit carryforwards expiration year	2031
Foreign Net Operating Loss Carryforwards
Income Tax [Line Items]
Net operating loss carryforwards	$ 149,400,000
Net operating loss carryforwards beginning expiration year	2022
Net operating loss carryforwards subject to expiration	$ 14,700,000
Net operating loss carryforwards indefinite carry forward period	$ 134,700,000