Retirement-Related Benefit Plans' Impact on Income Before Income Taxes (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Feb. 28, 2017	Feb. 29, 2016	Feb. 28, 2017	Feb. 29, 2016
Pension Benefits, U.S. Plans
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	$ 9,401	$ 8,202	$ 28,203	$ 24,606
Interest cost	4,331	4,499	12,993	13,497
Expected return on plan assets	(6,252)	(6,437)	(18,756)	(19,311)
Amortization of Prior service cost (credit)	54	58	162	174
Amortization of Net actuarial (gains) losses recognized	5,540	4,190	16,620	12,570
Net Periodic Benefit Cost	13,074	10,512	39,222	31,536
Pension Benefits, Non-U.S. Plans
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	1,127	1,067	3,381	3,201
Interest cost	1,224	1,319	3,672	3,965
Expected return on plan assets	(1,886)	(1,978)	(5,658)	(5,944)
Amortization of Net actuarial (gains) losses recognized	573	455	1,719	1,369
Settlement				91
Net Periodic Benefit Cost	1,038	863	3,114	2,682
Postretirement Benefits, U.S. Plans
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Interest cost	57	59	171	177
Amortization of Prior service cost (credit)	(58)	(62)	(174)	(186)
Net Periodic Benefit Cost	(1)	(3)	(3)	(9)
Postretirement Benefits, Non-U.S. Plans
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	284	281	852	843
Interest cost	222	221	666	663
Amortization of Net actuarial (gains) losses recognized	60	61	180	183
Net Periodic Benefit Cost	$ 566	$ 563	$ 1,698	$ 1,689

The amount of gains or losses recognized in net periodic benefit cost.

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- Definition

The amount of the prior service cost or credit recognized in net periodic benefit cost relating to benefit changes attributable to plan participants' prior service pursuant to a plan amendment or a plan initiation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (h)(1)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Prior Service Cost
-URI http://asc.fasb.org/extlink&oid=49177896

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- Definition

An amount calculated as a basis for determining the extent of delayed recognition of the effects of changes in the fair value of assets. The expected return on plan assets is determined based on the expected long-term rate of return on plan assets and the market-related value of plan assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Expected Return on Plan Assets
-URI http://asc.fasb.org/extlink&oid=6512171

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (h)(3)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920

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- Definition

The increase in a defined benefit pension plan's projected benefit obligation or a defined benefit postretirement plan's accumulated postretirement benefit obligation due to the passage of time.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (h)(2)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920

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- Definition

The total amount of net periodic benefit cost for defined benefit plans for the period. Periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (h)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920

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- Definition

Amount of net gain (loss) recognized in net periodic benefit cost as a result of an irrevocable action that relieves the employer (or the plan) of primary responsibility for a benefit obligation and eliminates significant risks related to the obligation and the assets used to effect the settlement. Examples of transactions that constitute a settlement include, but are not limited to, lump-sum cash payments to plan participants in exchange for their rights to receive specified benefits and purchasing nonparticipating annuity contracts to cover vested benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 30
-Section 15
-Paragraph 6
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=7577095&loc=d3e8001-114927

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (h)(7)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920

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- Definition

The actuarial present value of benefits attributed by the pension benefit formula to services rendered by employees during the period. The portion of the expected postretirement benefit obligation attributed to employee service during the period. The service cost component is a portion of the benefit obligation and is unaffected by the funded status of the plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Service Cost (Component of Net Periodic Pension Cost)
-URI http://asc.fasb.org/extlink&oid=6525008

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (h)(1)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920

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-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 1
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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