Description of Business and Summary of Significant Accounting Policies (Details 5) $ / shares in Units, $ in Millions	12 Months Ended
	May 31, 2016	May 31, 2015 USD ($) $ / shares
Impairment of Long Lived Assets [Abstract]
Number of Idle Aircraft	4
Number of months aircraft remained idle	less than 1 year
Number of Impaired Boeing MD11 Aircraft		7
Number of Impaired Boeing MD11 Aircraft Engines		12
Number of Impaired Airbus A310-300 Aircraft		4
Number of Impaired Airbus A310-300 Aircraft Engines		3
Number of Impaired Airbus A300-600 Aircraft		3
Number of Impaired Airbus A300-600 Aircraft Engines		3
Number of Impaired Boeing MD10-10 Aircraft		1
Number of Impaired Boeing MD10-10 Aircraft Engines		3
Asset impairments		$ 276
Asset impairments, net of tax		$ 175
Asset impairments Diluted EPS impact | $ / shares		$ 0.61
Asset impairment non-cash		$ 246