Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	5 Months Ended	7 Months Ended	12 Months Ended
	May 31, 2018	Dec. 31, 2017	May 31, 2019	May 31, 2018	May 31, 2017	May 23, 2018
Income Taxes [Line Items]
Federal statutory income tax rate	21.00%	35.00%	21.00%	29.20%	35.00%
Provisional income tax benefit related to re-measurement of deferred tax assets and liabilities				$ 38,200
Provisional income tax expense related to repatriation tax				6,900
Tax amount related to purchase of noncontrolling interest and its carrying value					$ 539
Tax benefits (expense) related to defined benefit pension liability credited to other comprehensive income			$ 418	(309)	(1,158)
Tax benefits (expenses) related to cash flow hedges credited to (deducted from) other comprehensive income			$ 3,780	$ (392)	$ 1,700
Effective tax rates upon inclusion of net earnings attributable to noncontrolling interests			20.90%	3.90%	26.70%
Minimum likelihood of tax benefits being recognized upon ultimate settlement			50.00%
Total unrecognized tax benefits	$ 2,638		$ 1,621	$ 2,638	$ 2,975
Unrecognized tax benefits if recognized would affect tax rate attributable to controlling interest			1,257
Interest and penalties related to unrecognized tax benefits	271		287	271	$ 307
Valuation allowance for deferred tax assets	$ 14,006		14,619	$ 14,006
Settlement with Taxing Authority
Income Taxes [Line Items]
Liability for unrecognized tax benefit expected to be settled in the next 12 months			1,000
State and Local Jurisdiction
Income Taxes [Line Items]
Net operating loss carry forwards			10,745
Valuation allowance for deferred tax assets			$ 9,341
State and Local Jurisdiction | Earliest Tax Year
Income Taxes [Line Items]
Operating loss carryforwards, expiration date			May 31, 2021
State and Local Jurisdiction | Latest Tax Year
Income Taxes [Line Items]
Operating loss carryforwards, expiration date			May 31, 2039
Non - United States
Income Taxes [Line Items]
Net operating loss carry forwards			$ 5,688
Valuation allowance for deferred tax assets			$ 5,278
Non - United States | Earliest Tax Year
Income Taxes [Line Items]
Operating loss carryforwards, expiration date			May 31, 2020
Non - United States | Latest Tax Year
Income Taxes [Line Items]
Operating loss carryforwards, expiration date			May 31, 2025
Worthington Aritas
Income Taxes [Line Items]
Ownership interest percentage						25.00%