Retirement Plans (Details 3) - USD ($) $ in Millions	6 Months Ended
	Nov. 30, 2015	Nov. 30, 2014
Pension Plans Contributions [Abstract]
Required U.S. pension plan contributions	$ 8	$ 247
Voluntary U.S. pension plan contributions	322	83
U.S. domestic pension contributions	330	$ 330
December 2015 U.S. Pension Plans contribution	$ 165