Assets Measured at Fair Value on Non-recurring Basis (Detail) (USD $)	May 31, 2014		May 31, 2013
Fair Value [Line Items]
Asset measured at fair value on nonrecurring basis	$ 32,074,000		$ 6,856,000
Long Lived Assets Held For Sale
Fair Value [Line Items]
Asset measured at fair value on nonrecurring basis	25,040,000	[1]
Long-lived assets held and used
Fair Value [Line Items]
Asset measured at fair value on nonrecurring basis	7,034,000	[2]	6,856,000	[3]
Significant Other Observable Inputs (Level 2)
Fair Value [Line Items]
Asset measured at fair value on nonrecurring basis	32,074,000		6,856,000
Significant Other Observable Inputs (Level 2) | Long Lived Assets Held For Sale
Fair Value [Line Items]
Asset measured at fair value on nonrecurring basis	25,040,000	[1]
Significant Other Observable Inputs (Level 2) | Long-lived assets held and used
Fair Value [Line Items]
Asset measured at fair value on nonrecurring basis	$ 7,034,000	[2]	$ 6,856,000	[3]

[1] During the fourth quarter of fiscal 2014, management committed to a plan to sell the Company's 60%-owned consolidated joint venture in India, Worthington Nitin Cylinders. In accordance with the applicable accounting guidance, the net assets were recorded at the lower of net book value or fair value less costs to sell. As the fair value of the asset group, or $5,925,000, was lower than its net book value, an impairment charge of $18,959,000 was recognized within impairment of long-lived assets in our fiscal 2014 consolidated statement of earnings. The portion of this impairment loss attributable to the noncontrolling interest, or $7,583,000, was recorded within net earnings attributable to noncontrolling interest in our fiscal 2014 consolidated statement of earnings. During the fourth quarter of fiscal 2014, management committed to plans to sell the Company's stainless steel business, Precision Specialty Metals, Inc. In accordance with the applicable accounting guidance, the net assets were recorded at the lower of net book value or fair value less costs to sell. As the fair value of the asset group, or $19,115,000, was lower than its net book value, an impairment charge of $7,141,000 was recognized within impairment of long-lived assets in our fiscal 2014 consolidated statement of earnings.

[2] During the fourth quarter of fiscal 2014, we determined that indicators of impairment were present at the Company's aluminum high-pressure cylinder business in New Albany, Mississippi, due to current and projected operating losses. Recoverability of the identified asset group was tested using future cash flow projections based on management's long-range estimates of market conditions. The sum of these undiscounted future cash flows was less than the net book value of the asset group. In accordance with the applicable accounting guidance, the net assets were written down to their fair value of $7,034,000, resulting in an impairment charge of $1,412,000 within impairment of long-lived assets in our fiscal 2014 consolidated statement of earnings.

[3] During the fourth quarter of fiscal 2013, the long-lived assets of our 60%-owned consolidated joint venture in India, Worthington Nitin Cylinders, were written down to their estimated fair value of $6,856,000, resulting in an impairment charge of $4,968,000 within impairment of long-lived assets in our consolidated statement of earnings. The portion of this impairment loss attributable to the noncontrolling interest, or $1,987,000, was recorded within net earnings attributable to noncontrolling interest in our consolidated statement of earnings. Fair value was determined based on market prices for similar assets.