Employee Benefit Plans - Schedule of targeted weighted average asset allocations (Details) - U.K. - Pension Plans	May 31, 2022	May 31, 2021
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Weighted average asset allocations	100.00%	100.00%
Targeted asset allocation	100.00%
Equity securities
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Weighted average asset allocations	56.10%	47.10%
Targeted asset allocation	56.00%
Cash and cash equivalents
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Weighted average asset allocations	1.10%	2.30%
Targeted asset allocation	1.00%
Liability-driven instruments
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Weighted average asset allocations	23.20%	31.80%
Targeted asset allocation	23.00%
Real estate
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Weighted average asset allocations	5.70%	4.20%
Targeted asset allocation	6.00%
Other
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Weighted average asset allocations	13.90%	14.60%
Targeted asset allocation	14.00%