Results of Reportable Segments (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Feb. 28, 2017	Feb. 29, 2016	Feb. 28, 2017	Feb. 29, 2016	May 31, 2016
Segment Reporting Information [Line Items]
Net Sales	$ 1,022,496	$ 988,555	$ 3,465,329	$ 3,387,065
Income Before Income Taxes	16,997	21,906	58,615	284,368
Identifiable Assets	4,732,219		4,732,219		$ 4,764,969
Operating Segments \| Industrial Segment
Segment Reporting Information [Line Items]
Net Sales	521,403	492,662	1,830,672	1,793,075
Income Before Income Taxes	11,705	486	151,262	148,962
Identifiable Assets	2,204,420		2,204,420		2,206,062
Operating Segments \| Specialty Segment
Segment Reporting Information [Line Items]
Net Sales	159,659	156,909	519,562	500,395
Income Before Income Taxes	15,000	21,729	76,664	76,496
Identifiable Assets	759,764		759,764		754,757
Operating Segments \| Consumer Segment
Segment Reporting Information [Line Items]
Net Sales	341,434	338,984	1,115,095	1,093,595
Income Before Income Taxes	29,802	38,785	(40,685)	170,337
Identifiable Assets	1,674,736		1,674,736		1,734,600
Corporate/Other
Segment Reporting Information [Line Items]
Income Before Income Taxes	(39,510)	$ (39,094)	(128,626)	$ (111,427)
Identifiable Assets	$ 93,299		$ 93,299		$ 69,550

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(12))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(11))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(h)(1)(i))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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