Investments In Unconsolidated Affiliates (Narrative) (Details) (USD $)	9 Months Ended		12 Months Ended					1 Months Ended
	Feb. 29, 2012	Feb. 29, 2012 Worthington Armstrong Venture [Member]	May 31, 2011 Worthington Armstrong Venture [Member]	Dec. 31, 2011 Worthington Armstrong Venture [Member]	Feb. 29, 2012 Joint Venture Transactions [Member] ArtiFlex [Member]	Feb. 29, 2012 Joint Venture Transactions [Member] ClarkDietrich [Member]	Feb. 29, 2012 Joint Venture Transactions [Member] Gestamp Worthington Wind Steel, LLC [Member]	Jan. 31, 2012 Joint Venture Transactions [Member] LEFCO Worthington, LLC [Member]	Feb. 29, 2012 Joint Venture Transactions [Member] Samuel Steel Pickling Company [Member]	Feb. 29, 2012 Joint Venture Transactions [Member] Serviacero Planos, S. de R.L. de C.V. [Member]	Feb. 29, 2012 Joint Venture Transactions [Member] TWB Company, L.L.C. [Member]	Feb. 29, 2012 Joint Venture Transactions [Member] Worthington Armstrong Venture [Member]	Feb. 29, 2012 Joint Venture Transactions [Member] Worthington Modern Steel Framing Manufacturing Co., Ltd. [Member]	Feb. 29, 2012 Joint Venture Transactions [Member] Worthington Specialty Processing [Member]
Investments in and Advances to Affiliates [Line Items]
Percent of interest by unconsolidated affiliates					50.00%	25.00%	50.00%		31.00%	50.00%	45.00%	50.00%	40.00%	51.00%
Sale of equity interest, percentage								49.00%
Distributions from unconsolidated affiliates	$ 116,348,000
Non-recurring special dividend received				50,000,000
Cumulative distributions in excess of investment		$ 64,263,000	$ 10,715,000