The interest rate used to adjust for the time value of money for the plan.

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

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- Definition

Expected rate of compensation increases (for pay-related plans).

+ 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 (k)(2)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920

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- Definition

An assumption as to the rate of return on plan assets reflecting the average rate of earnings expected on the funds invested or to be invested to provide for the benefits included in the benefit obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Expected Long-Term Rate of Return on Plan Assets
-URI http://asc.fasb.org/extlink&oid=6512046

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (k)(3)
-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.

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No definition available.

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Deferred Compensation And Retirement Plans (Weighted-Average Assumptions Used In Calculating The Benefit Obligations) (Detail)	5 Months Ended	12 Months Ended
	Apr. 30, 2016	Apr. 30, 2016	Apr. 30, 2015	Apr. 30, 2014
Deferred Compensation Plan
Defined Benefit Plan Disclosure [Line Items]
Discount rate, beginning of period		3.28%	3.60%	3.12%
Discount rate, end of period	3.05%	3.05%	3.28%	3.60%
Rate of compensation increase	0.00%	0.00%	0.00%	0.00%
Pension Plans, Defined Benefit
Defined Benefit Plan Disclosure [Line Items]
Discount rate, beginning of period		3.28%	3.60%	3.12%
Discount rate, end of period	3.05%	3.05%	3.28%	3.60%
Rate of compensation increase	0.00%	0.00%	0.00%	0.00%
Expected long-term rates of return on plan assets
Pension Plans, Defined Benefit \| Hay Group
Defined Benefit Plan Disclosure [Line Items]
Discount rate, beginning of period	4.10%
Discount rate, end of period	3.49%	3.49%
Rate of compensation increase	0.00%	0.00%
Expected long-term rates of return on plan assets	6.50%
Supplemental Pension Benefits \| Hay Group
Defined Benefit Plan Disclosure [Line Items]
Discount rate, beginning of period	4.10%
Discount rate, end of period	3.23%	3.23%
Rate of compensation increase	0.00%	0.00%
Expected long-term rates of return on plan assets	0.00%
Medical And Life Insurance \| Hay Group
Defined Benefit Plan Disclosure [Line Items]
Discount rate, beginning of period	4.10%
Discount rate, end of period	3.36%	3.36%
Rate of compensation increase	0.00%	0.00%
Expected long-term rates of return on plan assets	0.00%