Schedule of Consideration Transferred and Fair Value Assigned to Assets Acquired And Liabilities Assumed (Detail) (USD $)			9 Months Ended
	Feb. 28, 2014	May 31, 2013	Feb. 28, 2014 TWB	Feb. 28, 2014 Worthington Aritas
Consideration Transferred:
Cash consideration			$ 17,869,000
Fair value of previously held interest in TWB			72,369,000
Total consideration			90,238,000
Estimated Fair Value of Assets Acquired and Liabilities Assumed:
Cash and cash equivalents			70,826,000	1,037,000
Accounts receivable			52,012,000	3,326,000
Inventories			20,403,000	10,678,000
Prepaid expenses and other current assets			4,027,000	1,317,000
Intangible assets			22,028,000	16,800,000
Other noncurrent assets			103,000	1,099,000
Property, plant and equipment			52,390,000	5,467,000
Total identifiable assets			221,789,000	39,724,000
Accounts payable			(50,642,000)	(5,587,000)
Short-term borrowings				(251,000)
Accrued liabilities				(2,756,000)
Accrued liabilities			(6,431,000)	(4,954,000)
Deferred taxes			(2,109,000)	(2,787,000)
Net identifiable assets				23,389,000
Goodwill	237,553,000	213,858,000		23,586,000
Net assets			162,607,000	46,975,000
Noncontrolling interest			(72,369,000)	(11,744,000)
Total consideration			$ 90,238,000	$ 35,231,000