Business Segment Information - Geographic Data (Details) - USD ($) $ in Millions	12 Months Ended
May 31, 2026	May 31, 2025	May 31, 2024
Business Segment Information
Net sales	$ 3,308.0	$ 2,780.5	$ 2,318.9
Long-lived assets	1,613.8	1,334.0
UNITED STATES
Business Segment Information
Long-lived assets	1,370.3	1,110.8
Europe/Africa
Business Segment Information
Long-lived assets	96.7	93.8
Other
Business Segment Information
Long-lived assets	146.8	129.4
Foreign countries
Business Segment Information
Net sales	$ 1,135.4	$ 951.7	$ 770.0
Foreign countries \| Total sales \| Geographic concentration
Business Segment Information
Percentage of total sales	34.30%	34.20%	33.20%
Parts Supply
Business Segment Information
Net sales	$ 1,487.7	$ 1,099.6	$ 967.0
Parts Supply \| North America
Business Segment Information
Net sales	840.6	631.6	532.1
Parts Supply \| Europe/Africa
Business Segment Information
Net sales	331.4	263.2	252.9
Parts Supply \| Asia
Business Segment Information
Net sales	250.4	166.1	146.4
Parts Supply \| Other
Business Segment Information
Net sales	65.3	38.7	35.6
Repair, Engineering, and Software
Business Segment Information
Net sales	1,080.8	931.0	681.3
Repair, Engineering, and Software \| North America
Business Segment Information
Net sales	881.1	735.9	589.1
Repair, Engineering, and Software \| Europe/Africa
Business Segment Information
Net sales	99.7	100.1	55.0
Repair, Engineering, and Software \| Asia
Business Segment Information
Net sales	94.4	86.8	31.1
Repair, Engineering, and Software \| Other
Business Segment Information
Net sales	5.6	8.2	6.1
Government Solutions
Business Segment Information
Net sales	502.3	495.4	451.7
Government Solutions \| North America
Business Segment Information
Net sales	499.9	493.1	440.1
Government Solutions \| Europe/Africa
Business Segment Information
Net sales	2.1	2.1	11.3
Government Solutions \| Asia
Business Segment Information
Net sales	0.3	0.2	0.3
Legacy Commercial Programs
Business Segment Information
Net sales	237.2	254.5	218.9
Legacy Commercial Programs \| North America
Business Segment Information
Net sales	140.6	167.6	147.4
Legacy Commercial Programs \| Europe/Africa
Business Segment Information
Net sales	73.4	66.4	53.4
Legacy Commercial Programs \| Asia
Business Segment Information
Net sales	$ 23.2	$ 20.5	$ 18.1

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