Employee Pension Plans - Reconciliation of Changes in Projected Benefit Obligation and Fair Value of Plan Assets and Funded Status of Defined-benefit Plans (Detail) - USD ($) $ in Thousands	12 Months Ended
	May 31, 2023	May 31, 2022	May 31, 2021
Change in benefit obligation
Interest cost	$ 4,393	$ 2,621	$ 1,205
Change in plan assets
Return on plan assets	5,092	4,473	4,289
Pension Benefit
Change in benefit obligation
Benefit obligation, beginning of year	113,567	41,195
Interest cost	4,391	2,621
Actuarial gain	(5,420)	(24,755)
Benefits paid	(6,662)	(4,511)
Settlements	(9,446)	(2,929)
Benefit obligations acquired		101,946
Benefits obligation, end of year	96,430	113,567	41,195
Change in plan assets
Fair value, beginning of year	83,393	33,136
Return on plan assets	(1,137)	(11,379)
Company contributions	6,837	2,308
Benefits paid	(6,662)	(4,511)
Settlements	(9,446)	(2,929)
Plan assets acquired		66,768
Fair value, end of year	72,985	83,393	$ 33,136
Funded status	(23,445)	(30,174)
Amounts recognized in our consolidated balance sheets consist of:
Amounts recognized in our consolidated balance sheets	2,580	6,736
Amounts recognized in AOCI consist of:
Net loss (income)	2,580	6,736
Total	2,580	6,736
Other Benefits
Change in benefit obligation
Benefit obligation, beginning of year	4,077
Service cost	18	15
Interest cost	168	70
Plan amendments	(441)
Actuarial gain	(281)	(873)
Benefits paid	(174)	(125)
Participant contributions		8
Benefit obligations acquired		4,982
Benefits obligation, end of year	3,367	4,077
Change in plan assets
Company contributions	174	117
Benefits paid	(174)	(125)
Participant contributions		8
Funded status	(3,367)	(4,077)
Amounts recognized in our consolidated balance sheets consist of:
Amounts recognized in our consolidated balance sheets	1,544	(873)
Amounts recognized in AOCI consist of:
Net loss (income)	(1,103)	(873)
Net prior service (credit)/cost	(441)
Total	1,544	(873)
Other Liabilities | Pension Benefit
Amounts recognized in our consolidated balance sheets consist of:
Amounts recognized in our consolidated balance sheets	(23,445)	(30,174)
Amounts recognized in AOCI consist of:
Total	(23,445)	(30,174)
Other Liabilities | Other Benefits
Amounts recognized in our consolidated balance sheets consist of:
Amounts recognized in our consolidated balance sheets	(3,367)	(4,077)
Amounts recognized in AOCI consist of:
Total	(3,367)	(4,077)
AOCI | Pension Benefit
Amounts recognized in our consolidated balance sheets consist of:
Amounts recognized in our consolidated balance sheets	2,580	6,736
Amounts recognized in AOCI consist of:
Total	2,580	6,736
AOCI | Other Benefits
Amounts recognized in our consolidated balance sheets consist of:
Amounts recognized in our consolidated balance sheets	(1,544)	(873)
Amounts recognized in AOCI consist of:
Total	$ (1,544)	$ (873)