Employee Benefit Plans - Obligations and Funded Status (Details) - USD ($) $ in Thousands	12 Months Ended
	May 31, 2023	May 31, 2022
Change in benefit obligation:
Projected benefit obligation, beginning of year	$ 84,546	$ 99,728
Interest cost	3,089	2,148
Actuarial gain	(6,556)	(14,044)
Benefits paid	(3,340)	(3,286)
Projected benefit obligation, end of year	77,739	84,546
Change in plan assets:
Fair value of plan assets, beginning of year	66,723	78,244
Actual loss on plan assets	(3,345)	(8,322)
Employer contributions	0	87
Benefits paid	(3,340)	(3,286)
Fair value of plan assets, end of year	60,038	66,723
Funded status-net amount recognized	$ (17,701)	$ (17,823)