Employee Benefit Plans (Details) - Schedule of recognized in accumulated other comprehensive loss - USD ($) $ in Millions	May 31, 2018	May 31, 2017
Pension and postretirement adjustments:
Net actuarial gain (loss)	$ (13.8)	$ (70.9)
Amount recognized in Accumulated comprehensive income (loss) before tax	(13.8)	(70.9)
Other Postretirement Benefits [Member]
Pension and postretirement adjustments:
Net actuarial gain (loss)	(1.3)	(3.3)
Amount recognized in Accumulated comprehensive income (loss) before tax	(1.3)	(3.3)
U.S. [Member] | Pension Plans [Member]
Pension and postretirement adjustments:
Net actuarial gain (loss)	0.0	(51.3)
Amount recognized in Accumulated comprehensive income (loss) before tax	0.0	(51.3)
U.K. [Member] | Pension Plans [Member]
Pension and postretirement adjustments:
Net actuarial gain (loss)	(12.5)	(16.3)
Amount recognized in Accumulated comprehensive income (loss) before tax	$ (12.5)	$ (16.3)