Employee Benefit Plans - Weighted Average Assumptions Used to Determine Benefit Obligations (Details)	12 Months Ended
May 31, 2018	May 31, 2017
Retirement Benefits [Abstract]
Discount rate (as a percent)	3.95%	3.79%
Discount rate (as a percent)	3.79%	4.00%
Expected return on plan assets (as a percent)	4.90%	5.40%

No definition available.

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- Definition

Weighted average rate for present value of future retirement benefits cash flows, used to determine benefit obligation of defined benefit plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (k)(1)
-URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920

+ Details

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- Definition

Weighted average rate for present value of future retirement benefits cash flows, used to determine net periodic benefit cost of defined benefit plan.

+ References

+ Details

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- Definition

Weighted average rate of return on plan assets, reflecting average rate of earnings expected on existing plan assets and expected contributions, used to determine net periodic benefit cost of defined benefit plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (k)(3)
-URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920

+ Details

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