CONSOLIDATED STATEMENTS OF EQUITY - USD ($) shares in Millions, $ in Millions	TOTAL ECOLAB SHAREHOLDERS' EQUITY	COMMON STOCK	ADDITIONAL PAID-IN CAPITAL	RETAINED EARNINGS	ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS)	TREASURY STOCK	NON-CONTROLLING INTEREST	Total
Balance at Dec. 31, 2021	$ 7,224.2	$ 364.1	$ 6,464.6	$ 8,814.5	$ (1,634.8)	$ (6,784.2)	$ 28.9	$ 7,253.1
Increase (Decrease) in Stockholders' Equity
Net income	827.3			827.3			12.1	839.4
Other comprehensive income (loss) activity	(195.7)				(195.7)		(6.0)	(201.7)
Cash dividends declared (a)	(436.7)			(436.7)			(8.3)	(445.0)
Fair value adjustment of prior acquisition							0.6	0.6
Stock options and awards	88.9	0.5	87.2			1.2		88.9
Reacquired shares	(445.4)					(445.4)		(445.4)
Balance at Sep. 30, 2022	7,062.6	364.6	6,551.8	9,205.1	(1,830.5)	(7,228.4)	27.3	7,089.9
Balance at Jun. 30, 2022	7,093.4	364.5	6,529.8	9,003.3	(1,617.9)	(7,186.3)	25.0	7,118.4
Increase (Decrease) in Stockholders' Equity
Net income	347.1			347.1			4.9	352.0
Other comprehensive income (loss) activity	(212.6)				(212.6)		(2.1)	(214.7)
Cash dividends declared (a)	(145.3)			(145.3)			(0.5)	(145.8)
Stock options and awards	22.6	0.1	22.0			0.5		22.6
Reacquired shares	(42.6)					(42.6)		(42.6)
Balance at Sep. 30, 2022	7,062.6	364.6	6,551.8	9,205.1	(1,830.5)	(7,228.4)	27.3	7,089.9
Balance at Dec. 31, 2022	7,236.1	364.7	6,580.2	9,318.8	(1,726.6)	(7,301.0)	22.5	$ 7,258.6
Balance (in shares) at Dec. 31, 2022								284.5
Increase (Decrease) in Stockholders' Equity
Net income	967.1			967.1			15.1	$ 982.2
Other comprehensive income (loss) activity	(74.8)				(74.8)		(0.9)	(75.7)
Cash dividends declared (a)	(453.1)			(453.1)			(10.0)	(463.1)
Changes in noncontrolling interest	(4.5)		(4.5)					(4.5)
Stock options and awards	136.7	0.7	134.4			1.6		136.7
Reacquired shares	(11.7)					(11.7)		(11.7)
Balance at Sep. 30, 2023	7,795.8	365.4	6,710.1	9,832.8	(1,801.4)	(7,311.1)	26.7	$ 7,822.5
Balance (in shares) at Sep. 30, 2023								285.1
Balance at Jun. 30, 2023	7,556.7	365.3	6,684.1	9,580.0	(1,761.8)	(7,310.9)	23.8	$ 7,580.5
Increase (Decrease) in Stockholders' Equity
Net income	404.0			404.0			5.4	409.4
Other comprehensive income (loss) activity	(39.6)				(39.6)		0.6	(39.0)
Cash dividends declared (a)	(151.2)			(151.2)			(3.1)	(154.3)
Stock options and awards	26.6	0.1	26.0			0.5		26.6
Reacquired shares	(0.7)					(0.7)		(0.7)
Balance at Sep. 30, 2023	$ 7,795.8	$ 365.4	$ 6,710.1	$ 9,832.8	$ (1,801.4)	$ (7,311.1)	$ 26.7	$ 7,822.5
Balance (in shares) at Sep. 30, 2023								285.1