OPERATING SEGMENTS - Reportable segment information (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025
OPERATING SEGMENTS
Net Sales	$ 4,066.1	$ 3,695.0
Cost of sales	2,295.3	2,060.2
Selling, general and administrative expenses	1,102.4	1,050.0
Special (gains) and charges	46.4	29.5
Operating Income (Loss)	622.0	555.3
Operating segment
OPERATING SEGMENTS
Net Sales	4,053.9	3,823.1
Cost of sales	2,288.2	2,131.6
Selling, general and administrative expenses	1,100.7	1,080.1
Special (gains) and charges	45.3	29.1
Operating Income (Loss)	619.7	582.3
Currency impact
OPERATING SEGMENTS
Net Sales	12.2	(128.1)
Operating Income (Loss)	2.3	(27.0)
Global Water
OPERATING SEGMENTS
Net Sales	2,043.0	1,826.4
Global Water \| Operating segment
OPERATING SEGMENTS
Net Sales	2,035.2	1,899.5
Cost of sales	1,239.1	1,131.1
Selling, general and administrative expenses	498.3	489.7
Operating Income (Loss)	297.8	278.7
Global Institutional and Specialty
OPERATING SEGMENTS
Net Sales	1,511.4	1,418.0
Global Institutional and Specialty \| Operating segment
OPERATING SEGMENTS
Net Sales	1,507.7	1,454.8
Cost of sales	751.0	731.4
Selling, general and administrative expenses	409.2	415.0
Operating Income (Loss)	347.5	308.4
Global Pest Elimination
OPERATING SEGMENTS
Net Sales	310.8	280.6
Global Pest Elimination \| Operating segment
OPERATING SEGMENTS
Net Sales	310.1	287.4
Cost of sales	178.8	166.9
Selling, general and administrative expenses	79.6	72.8
Operating Income (Loss)	51.7	47.7
Global Life Sciences
OPERATING SEGMENTS
Net Sales	200.9	170.0
Global Life Sciences \| Operating segment
OPERATING SEGMENTS
Net Sales	200.9	181.4
Cost of sales	108.0	97.4
Selling, general and administrative expenses	55.4	53.0
Operating Income (Loss)	37.5	31.0
Corporate \| Operating segment
OPERATING SEGMENTS
Cost of sales	11.3	4.8
Selling, general and administrative expenses	58.2	49.6
Special (gains) and charges	45.3	29.1
Operating Income (Loss)	$ (114.8)	$ (83.5)

The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities.

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