Fair Value - Assets Measured at Fair Value on Non-Recurring Basis (Parenthetical) (Detail) - USD ($)		3 Months Ended
	Nov. 01, 2019	Aug. 31, 2020		May 31, 2020		Feb. 29, 2020	Aug. 31, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair market value of assets				$ 2,800,000
Fair Value, Measurements, Nonrecurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair market value of assets		$ 9,593,000		26,984,000
Engineered Cabs
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impairment of ROU assets							$ 905,000
Engineered Cabs | Noncontrolling Interests
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Percent of ownership interest held in unconsolidated affiliates	20.00%
Fair value of acquisition date	$ 13,623,000
Oil And Gas Operations | Fair Value, Measurements, Nonrecurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair market value of assets						$ 3,384,000
TWB Hermosillo
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impairment of ROU assets				565,000
Engineered Cabs Operating Segment
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impairment charge							1,469,000
Impairment of ROU assets							$ 3,938,000
Nisshin Joint Venture | Noncontrolling Interests
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Percent of ownership interest held in unconsolidated affiliates							10.00%
WSP Joint Venture
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impairment charge						1,274,000
WSP Joint Venture | Fair Value, Measurements, Nonrecurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair market value of assets						700,000
Customer Lists | Cryogenics
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impairment charge		3,662,000
Long Lived Assets Held And Used | Fair Value, Measurements, Nonrecurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair market value of assets		9,593,000	[1],[2]	9,277,000	[3],[4],[5],[6],[7],[8]
Long Lived Assets Held And Used | Engineered Cabs | Fair Value, Measurements, Nonrecurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair market value of assets							$ 12,860,000
Long Lived Assets Held And Used | Packing Solutions Business
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair market value of assets				266,000
Long Lived Assets Held And Used | Packing Solutions Business | Fair Value, Measurements, Nonrecurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Carrying value long-lived assets				$ 2,810,000
Long Lived Assets Held And Used | Cryogenics
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Carrying value long-lived assets		13,526,000
Fair market value of assets		9,193,000
Long Lived Assets Held And Used | Jefferson | Alternative Fuel Cylinders Manufacturing Line Facility
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair market value of assets		400,000
Carrying value long-lived assets		$ 1,823,000
Fixed Assets [Member] | Oil And Gas Operations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair market value of assets						6,211,000
Goodwill | Oil And Gas Operations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impairment charge						$ 22,097,000

[1] During the quarter, management determined indicators of impairment were present with regard to the cryogenics business primarily operated out of Theodore, Alabama with European distribution in Austria.  As a result, long-lived assets with a carrying value of $13,526,000 were written down to their estimated fair value of $9,193,000.  Additionally, the customer list intangible assets with a carrying value of $3,662,000 were deemed to be fully impaired and written off.

[2] During the quarter, the Company decided to discontinue its operation of the manufacturing line for alternative fuel cylinders at the Jefferson, Ohio facility.  As a result, long-lived assets with a carrying value of $1,823,000 were written down to their estimated fair market value of $400,000.

[3] During the fourth quarter of fiscal 2020, the Company identified an impairment indicator related to the TWB Hermosillo facility operating lease due to the economic impact of COVID-19.  As a result, the lease ROU asset with a net book value of $565,000 was deemed fully impaired and written off.

[4] During the third quarter of fiscal 2020, the Company identified an impairment indicator for the oil & gas equipment business and performed an interim impairment test of the reporting unit.  In accordance with the applicable accounting guidance, the book value of the corresponding goodwill was written off, resulting in an impairment charge of $22,097,000.

[5] In May 2020, the Company committed to a plan to shut down the packaging solutions business in Greensburg, Indiana.  As a result, long-lived assets with a carrying value of $2,810,000 were written down to their estimated fair market value of $266,000.

[6] During the first quarter of fiscal 2020, the Company identified an impairment indicator for the fabricated products business in Stow, Ohio within the former Engineered Cabs operating segment.  As a result, fixed assets with a net book value of $1,469,000 and lease ROU assets with a net book value of $3,938,000 were deemed to be fully impaired and written off.

[7] During the fourth quarter of 2020, in connection with the annual indefinite lived assets impairment test, certain European tradenames were written down to their estimated fair market value of $2,800,000.

[8] During the third quarter of fiscal 2020, in connection with the closure of the oil & gas equipment manufacturing operations in Wooster, Ohio, customer list intangible assets were determined to be fully impaired and written off.  In addition, the remaining fixed assets at Wooster, Ohio were written down to their estimated fair market value of $6,211,000.