Debt - Summary of Debt Outstanding (Detail) - USD ($) $ in Millions		3 Months Ended
		Aug. 31, 2025	May 31, 2025	Dec. 17, 2024
Long-term debt:
Total		$ 73.4	$ 2.3
Less: current maturities of long-term debt		30.3	0.0
Long-term debt, net of current maturities		43.1	2.3
Short-term borrowing and current maturities:
Total short-term borrowings and current maturities		190.3	149.2
Total Debt		233.4	151.5
FED DEV Loan
Long-term debt:
Rate				0.00%
Long-term debt, net of current maturities		2.3	2.3
FED DEV Loan | Unsecured
Long-term debt:
Total		$ 2.3	2.3
Maturity		Mar. 31, 2032
BDC Loan | Secured
Long-term debt:
Total		$ 21.6
Maturity		Jun. 30, 2051
AMIC Loan | Unsecured
Long-term debt:
Total		$ 0.7
Maturity		May 31, 2032
AMIC Loan | Unsecured | Minimum
Long-term debt:
Rate		0.00%
AMIC Loan | Unsecured | Maximum
Long-term debt:
Rate		5.97%
Sitem Group Term Loan 1 | Unsecured
Long-term debt:
Total	[1]	$ 3.7
Maturity		Jun. 30, 2029
Sitem Group Term Loan 2 | Unsecured
Long-term debt:
Total		$ 1.3
Rate		1.50%
Maturity		Mar. 31, 2027
Sitem Group Term Loan 3 | Secured
Long-term debt:
Total		$ 4.4
Rate		1.94%
Maturity		Sep. 30, 2030
Sitem Group Term Loan 4 | Unsecured
Long-term debt:
Total		$ 0.2
Rate		0.36%
Maturity		Feb. 28, 2029
Sitem Group Term Loan 5 | Unsecured
Long-term debt:
Total	[2]	$ 3.5
Maturity		Mar. 31, 2029
Sitem Group Term Loan 6 | Unsecured
Long-term debt:
Total		$ 0.8
Rate		0.55%
Maturity		Dec. 31, 2028
Sitem Group Term Loan 7 | Unsecured
Long-term debt:
Total	[2]	$ 1.1
Maturity		Mar. 31, 2027
Sitem Group Term Loan 8 | Secured
Long-term debt:
Total		$ 1.3
Maturity		May 31, 2026
Sitem Group Term Loan 9 | Secured
Long-term debt:
Total	[3]	$ 6.5
Maturity		Mar. 31, 2030
Sitem Group Term Loan 10 | Secured
Long-term debt:
Total		$ 0.5
Maturity		Sep. 30, 2026
Sitem Group Term Loan 11 | Unsecured
Long-term debt:
Total		$ 4.0
Maturity		Mar. 31, 2028
Sitem Group Term Loan 12 | Unsecured
Long-term debt:
Total		$ 0.4
Rate		0.65%
Maturity		Nov. 30, 2025
Sitem Group Term Loan 13 | Secured
Long-term debt:
Total		$ 0.1
Rate		0.90%
Maturity		Oct. 31, 2026
Standstill Agreement - Sitem Group | Secured
Long-term debt:
Total		$ 21.0
Maturity		Jun. 30, 2026
BDC Floating Base Rate | BDC Loan | Secured
Long-term debt:
Rate		1.75%
Euribor 3m/360 | Sitem Group Term Loan 1 | Unsecured
Long-term debt:
Rate	[1]	1.50%
Euribor 3m/360 | Sitem Group Term Loan 5 | Unsecured
Long-term debt:
Rate	[2]	1.60%
Euribor 3m/360 | Sitem Group Term Loan 9 | Secured
Long-term debt:
Rate	[3]	1.90%
Euribor 3m/360 | Sitem Group Term Loan 10 | Secured
Long-term debt:
Rate		1.20%
Euribor 3m/360 | Sitem Group Term Loan 11 | Unsecured
Long-term debt:
Rate		1.65%
Euribor 1m/360 | Sitem Group Term Loan 7 | Unsecured
Long-term debt:
Rate	[2]	1.40%
Euribor 1m/360 | Sitem Group Term Loan 8 | Secured
Long-term debt:
Rate		1.65%
SARON | Standstill Agreement - Sitem Group | Secured
Long-term debt:
Rate		0.00%
Rate		5.00%
Revolving Credit Facility
Short-term borrowing and current maturities:
Total short-term borrowings and current maturities		$ 160.0	$ 149.2
Revolving Credit Facility | Secured
Long-term debt:
Maturity		Nov. 30, 2028

[1] Sitem Group shall maintain a ratio of bank debt plus financial lease obligations less cash and cash equivalents (“Net Financial Position” or “NFP”) to net earnings before interest, tax, depreciation and amortization (“EBITDA”) less than or equal to 3, and a ratio of NFP to Equity less than or equal to 1.

[2] Sitem Group shall maintain a ratio of NFP to EBITDA less than or equal to 3, a ratio of NFP to Equity less than or equal to 1, a ratio of EBITDA to financial expenses less than or equal to 10, and a NFP less than or equal to €40.0 million (approximately USD $45.7 million as of August 31, 2025).

[3] Sitem Group shall maintain a ratio of NFP to EBITDA less than or equal to 3.60, a ratio of NFP to Equity less than or equal to 1.20, a ratio of EBITDA to financial expenses less than or equal to 8, and a NFP less than or equal to €48.0 million (approximately USD $54.8 million as of August 31, 2025).