CONSOLIDATED STATEMENTS OF EQUITY - USD ($) shares in Millions, $ in Millions	Ecolab Shareholders' Equity	Common Stock	Additional Paid-in Capital	Retained Earnings	AOCI (Loss)	Treasury Stock	Non-Controlling Interest	Total
Balance, beginning at Dec. 31, 2023	$ 8,044.7	$ 365.7	$ 6,766.7	$ 10,075.4	$ (1,850.4)	$ (7,312.7)	$ 27.5	$ 8,072.2
Increase (Decrease) in Stockholders' Equity
Net income	903.0			903.0			8.6	911.6
Other comprehensive income (loss) activity	(49.0)				(49.0)		(0.5)	(49.5)
Cash dividends declared (a)	(325.1)			(325.1)			(15.1)	(340.2)
Stock options and awards	238.2	1.4	235.4			1.4		238.2
Reacquired shares	(524.4)					(524.4)		(524.4)
Balance, Ending at Jun. 30, 2024	8,287.4	367.1	7,002.1	10,653.3	(1,899.4)	(7,835.7)	20.5	8,307.9
Balance, beginning at Mar. 31, 2024	8,205.6	366.8	6,917.6	10,324.5	(1,881.2)	(7,522.1)	20.0	8,225.6
Increase (Decrease) in Stockholders' Equity
Net income	490.9			490.9			4.1	495.0
Other comprehensive income (loss) activity	(18.2)				(18.2)		(1.0)	(19.2)
Cash dividends declared (a)	(162.1)			(162.1)			(2.6)	(164.7)
Stock options and awards	85.6	0.3	84.5			0.8		85.6
Reacquired shares	(314.4)					(314.4)		(314.4)
Balance, Ending at Jun. 30, 2024	8,287.4	367.1	7,002.1	10,653.3	(1,899.4)	(7,835.7)	20.5	8,307.9
Balance, beginning at Dec. 31, 2024	8,757.3	367.8	7,159.6	11,517.1	(1,982.0)	(8,305.2)	31.9	$ 8,789.2
Balance, beginning (in shares) at Dec. 31, 2024								283.4
Increase (Decrease) in Stockholders' Equity
Net income	926.7			926.7			8.3	$ 935.0
Other comprehensive income (loss) activity	(21.3)				(21.3)		1.6	(19.7)
Cash dividends declared (a)	(368.7)			(368.7)			(11.5)	(380.2)
Stock options and awards	215.8	1.0	212.7			2.1		215.8
Reacquired shares	(189.5)					(189.5)		(189.5)
Balance, Ending at Jun. 30, 2025	9,320.3	368.8	7,372.3	12,075.1	(2,003.3)	(8,492.6)	30.3	$ 9,350.6
Balance, Ending (in shares) at Jun. 30, 2025								283.6
Balance, beginning at Mar. 31, 2025	8,875.8	368.6	7,298.2	11,735.2	(2,064.2)	(8,462.0)	27.9	$ 8,903.7
Increase (Decrease) in Stockholders' Equity
Net income	524.2			524.2			4.3	528.5
Other comprehensive income (loss) activity	60.9				60.9		1.8	62.7
Cash dividends declared (a)	(184.3)			(184.3)			(3.7)	(188.0)
Stock options and awards	75.1	0.2	74.1			0.8		75.1
Reacquired shares	(31.4)					(31.4)		(31.4)
Balance, Ending at Jun. 30, 2025	$ 9,320.3	$ 368.8	$ 7,372.3	$ 12,075.1	$ (2,003.3)	$ (8,492.6)	$ 30.3	$ 9,350.6
Balance, Ending (in shares) at Jun. 30, 2025								283.6