Debt and Receivables Securitization - Additional Information (Detail) - USD ($)						12 Months Ended
	Sep. 26, 2014	Apr. 15, 2014	Aug. 10, 2012	Apr. 27, 2012	Apr. 13, 2010	May 31, 2016	May 31, 2015	May 31, 2014	Oct. 15, 2014
Debt And Receivables Securitization [Line Items]
Short-term borrowings						$ 2,651,000	$ 90,550,000
Letter of credit amount outstanding						$ 16,428,000
Interest Rate Swap
Debt And Receivables Securitization [Line Items]
Interest rate swap, interest rate									2.015%
Interest rate swap, start date						Dec. 26, 2014
Interest rate swap, maturity date						Sep. 26, 2019
Line of Credit Facility, Outstanding Borrowing Percentage									60.00%
4.55% Senior Notes due April 15, 2026
Debt And Receivables Securitization [Line Items]
Principal amount		$ 250,000,000
Debt, maturity date						Apr. 15, 2026
Debt, interest rate		4.55%				4.55%	4.55%
Percentage of principal amount debt instrument was sold to the public		99.789%
Yield to maturity		4.573%
Debt discount		$ 528,000				$ 433,000
Debt issuance cost		2,256,000
Settlement of hedge interest		$ (3,081,000)
Unamortized portion of debt issuance costs						$ 1,867,000
4.60% Senior Notes due August 10, 2024
Debt And Receivables Securitization [Line Items]
Principal amount			$ 150,000,000
Debt, maturity date			Aug. 10, 2024			Aug. 10, 2024
Debt, interest rate			4.60%			4.60%	4.60%
6.50% Unsecured Senior Notes due April 15, 2020
Debt And Receivables Securitization [Line Items]
Principal amount					$ 150,000,000
Debt, maturity date						Apr. 15, 2020
Debt, interest rate					6.50%
Yield to maturity					6.515%
Debt discount					$ 165,000	$ 63,000
Debt issuance cost					1,535,000
Settlement of hedge interest					$ (1,358,000)
Unamortized portion of debt issuance costs						569,000
Percentage of principal amount debt instrument was sold to the public					99.89%
Term Loan maturing May 1, 2019
Debt And Receivables Securitization [Line Items]
Maximum borrowing capacity				$ 5,880,000
Borrowings outstanding						$ 2,575,000
Term loan credit facility, term				7 years
Debt, maturity date						May 01, 2019
Debt, interest rate				2.49%
Debt instrument required monthly payments				$ 76,350
Securities Sold under Agreements to Repurchase
Debt And Receivables Securitization [Line Items]
Maturity date						2018-01
Maximum borrowing capacity						$ 100,000,000
Number of days past due trade accounts receivables are ineligible for securitization						90 days
Borrowings outstanding						$ 0
Facility fee						540,000	$ 723,000	$ 652,000
Worthington Aritas
Debt And Receivables Securitization [Line Items]
Short-term borrowings						2,651,000
Borrowings outstanding						$ 28,445,000
Term loan credit facility, term	5 years
Line of credit, variable rate						1.50%
Unsecured Revolving Credit Facility
Debt And Receivables Securitization [Line Items]
Maturity date						2020-04
Maximum borrowing capacity						$ 500,000,000
Borrowings outstanding						$ 0
Unsecured Revolving Credit Facility | Maximum
Debt And Receivables Securitization [Line Items]
Debt maturity period						1 year