Employee Benefit Plans (Details) - Schedule of change in benefit obligations - USD ($) $ in Millions	12 Months Ended
	May 31, 2020	May 31, 2019	May 31, 2018
Pension Plans [Member]
Change in benefit obligation:
Plan amendments	$ 0.0	$ 0.1
Other Postretirement Benefits [Member]
Change in benefit obligation:
Benefit obligation at beginning of year	23.4	26.8
Service cost	0.0	0.0	$ 0.0
Interest cost	0.6	0.8	0.8
Plan participants’ contributions	0.2	0.4
Actuarial losses (gains)	(1.3)	0.1
Foreign currency translation	0.0	0.0
Plan amendments	0.0	(2.7)
Benefits paid, including expenses	(2.1)	(2.0)
Benefit obligation at end of year	20.8	23.4	26.8
U.S. [Member] | Pension Plans [Member]
Change in benefit obligation:
Service cost			0.0
Interest cost			1.9
U.K. [Member] | Pension Plans [Member]
Change in benefit obligation:
Benefit obligation at beginning of year	40.9	40.0
Service cost	0.0	0.0	0.0
Interest cost	0.9	0.9	1.1
Plan participants’ contributions	0.0	0.0
Actuarial losses (gains)	2.4	3.1
Foreign currency translation	(1.1)	(2.0)
Benefits paid, including expenses	(1.4)	(1.2)
Benefit obligation at end of year	$ 41.7	$ 40.9	$ 40.0