Retirement Plans - Schedule of Weighted Average Actuarial Assumptions Used to Determine the Benefit Obligations and Net Periodic Benefit Cost of our Plans (Details)	12 Months Ended
	May 31, 2017	May 31, 2016	May 31, 2015
U.S. Pension Plans [Member]
Defined Benefit Plan Assumptions Used In Calculations [Abstract]
Discount rate used to determine benefit obligation	4.08%	4.13%	4.42%
Discount rate used to determine net periodic benefit cost	4.13%	4.42%	4.60%
Rate of increase in future compensation levels used to determine benefit obligation	4.47%	4.46%	4.62%
Rate of increase in future compensation levels used to determine net periodic benefit cost	4.46%	4.62%	4.56%
Expected long-term rate of return on assets	6.50%	6.50%	7.75%
U.S. Pension Plans [Member] | Segment [Member]
Defined Benefit Plan Assumptions Used In Calculations [Abstract]
Expected long-term rate of return on assets	6.50%	6.50%	6.50%
International Pension Plans [Member]
Defined Benefit Plan Assumptions Used In Calculations [Abstract]
Discount rate used to determine benefit obligation	2.43%	2.46%	2.95%
Discount rate used to determine net periodic benefit cost	2.46%	2.95%	3.57%
Rate of increase in future compensation levels used to determine benefit obligation	2.42%	2.82%	3.19%
Rate of increase in future compensation levels used to determine net periodic benefit cost	2.82%	3.19%	3.31%
International Pension Plans [Member] | Segment [Member]
Defined Benefit Plan Assumptions Used In Calculations [Abstract]
Expected long-term rate of return on assets	3.18%	3.68%	5.13%
Postretirement Healthcare Plans [Member]
Defined Benefit Plan Assumptions Used In Calculations [Abstract]
Discount rate used to determine benefit obligation	4.32%	4.43%	4.60%
Discount rate used to determine net periodic benefit cost	4.43%	4.62%	4.70%