XML 113 R98.htm IDEA: XBRL DOCUMENT v3.7.0.1
Employee Benefit Plans (Details) - Assumed health care cost trend rates
12 Months Ended
May 31, 2017
May 31, 2016
Assumed health care cost trend rates [Abstract]    
Health care cost trend rate assumed for the next fiscal year 7.00% 7.00%
Rate to which the cost trend is assumed to decline (the ultimate trend rate) 5.00% 5.00%
Year that the rate reaches the ultimate trend rate 2024 2024