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