Business Segment Information - Geographic Data (Details) - USD ($) $ in Millions	12 Months Ended
May 31, 2025	May 31, 2024	May 31, 2023
Business Segment Information
Net sales	$ 2,780.5	$ 2,318.9	$ 1,990.5
Long-lived assets	1,334.0	1,380.4
UNITED STATES
Business Segment Information
Long-lived assets	1,110.8	1,174.6
Europe/Africa
Business Segment Information
Long-lived assets	93.8	90.9
Other
Business Segment Information
Long-lived assets	129.4	114.9
Foreign countries
Business Segment Information
Net sales	$ 951.7	$ 770.0	$ 588.6
Foreign countries \| Total sales \| Geographic concentration
Business Segment Information
Percentage of total sales	34.20%	33.20%	29.60%
Parts Supply
Business Segment Information
Net sales	$ 1,099.6	$ 967.0	$ 818.4
Parts Supply \| North America
Business Segment Information
Net sales	631.6	532.1	493.3
Parts Supply \| Europe/Africa
Business Segment Information
Net sales	263.2	252.9	190.8
Parts Supply \| Asia
Business Segment Information
Net sales	166.1	146.4	108.9
Parts Supply \| Other
Business Segment Information
Net sales	38.7	35.6	25.4
Repair & Engineering
Business Segment Information
Net sales	884.9	640.1	533.4
Repair & Engineering \| North America
Business Segment Information
Net sales	715.8	572.1	488.6
Repair & Engineering \| Europe/Africa
Business Segment Information
Net sales	89.6	40.6	25.2
Repair & Engineering \| Asia
Business Segment Information
Net sales	75.8	24.6	12.0
Repair & Engineering \| Other
Business Segment Information
Net sales	3.7	2.8	7.6
Integrated Solutions
Business Segment Information
Net sales	695.3	641.9	546.9
Integrated Solutions \| North America
Business Segment Information
Net sales	581.3	536.0	461.7
Integrated Solutions \| Europe/Africa
Business Segment Information
Net sales	78.0	78.0	51.4
Integrated Solutions \| Other
Business Segment Information
Net sales	36.0	27.9	33.8
Expeditionary Services
Business Segment Information
Net sales	100.7	69.9	91.8
Expeditionary Services \| North America
Business Segment Information
Net sales	99.4	68.6	89.6
Expeditionary Services \| Other
Business Segment Information
Net sales	$ 1.3	$ 1.3	$ 2.2

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