CONSOLIDATED STATEMENT OF EQUITY - USD ($) $ in Millions	Ecolab Shareholders Equity	Common Stock	Additional Paid-in Capital	Retained Earnings	OCI (Loss)	Treasury Stock	Non-Controlling Interest	Total
Balance at Dec. 31, 2018	$ 8,003.2	$ 357.0	$ 5,633.2	$ 8,909.5	$ (1,761.7)	$ (5,134.8)	$ 50.4	$ 8,053.6
Increase (Decrease) in Stockholders' Equity
New accounting guidance adoption	(2.8)			58.4	(61.2)			(2.8)
Net income	665.1			665.1			7.5	672.6
Other comprehensive income (loss) activity	(13.5)				(13.5)		1.8	(11.7)
Cash dividends declared	(265.0)			(265.0)			(15.7)	(280.7)
Stock options and awards	185.9	1.9	182.5			1.5		185.9
Reacquired shares	(347.5)					(347.5)		(347.5)
Balance at Jun. 30, 2019	8,225.4	358.9	5,815.7	9,368.0	(1,836.4)	(5,480.8)	44.0	8,269.4
Balance at Mar. 31, 2019	8,220.7	358.2	5,731.0	9,131.8	(1,734.9)	(5,265.4)	46.2	8,266.9
Increase (Decrease) in Stockholders' Equity
Net income	368.6			368.6			3.6	372.2
Other comprehensive income (loss) activity	(101.5)				(101.5)		0.9	(100.6)
Cash dividends declared	(132.4)			(132.4)			(6.7)	(139.1)
Stock options and awards	86.0	0.7	84.7			0.6		86.0
Reacquired shares	(216.0)					(216.0)		(216.0)
Balance at Jun. 30, 2019	8,225.4	358.9	5,815.7	9,368.0	(1,836.4)	(5,480.8)	44.0	8,269.4
Balance at Dec. 31, 2019	8,685.3	359.6	5,907.1	9,993.7	(2,089.7)	(5,485.4)	40.5	8,725.8
Increase (Decrease) in Stockholders' Equity
New accounting guidance adoption	(4.3)			(4.3)				(4.3)
Net income	(1,751.6)			(1,751.6)			11.9	(1,739.7)
Other comprehensive income (loss) activity	100.0				100.0		0.2	100.2
Cash dividends declared	(270.0)			(270.0)			(11.7)	(281.7)
Separation of ChampionX	(1,059.9)		(8.5)			(1,051.4)	3.4	(1,056.5)
Changes in noncontrolling interest	17.6		17.6				(9.3)	8.3
Stock options and awards	242.8	2.4	238.8			1.6		242.8
Reacquired shares	(104.7)					(104.7)		(104.7)
Balance at Jun. 30, 2020	5,855.2	362.0	6,155.0	7,967.8	(1,989.7)	(6,639.9)	35.0	5,890.2
Balance at Mar. 31, 2020	8,822.1	360.8	6,018.1	10,136.9	(2,113.7)	(5,580.0)	38.5	8,860.6
Increase (Decrease) in Stockholders' Equity
Net income	(2,035.0)			(2,035.0)			5.1	(2,029.9)
Other comprehensive income (loss) activity	124.0				124.0		(0.2)	123.8
Cash dividends declared	(134.1)			(134.1)			(1.8)	(135.9)
Separation of ChampionX	(1,059.9)		(8.5)			(1,051.4)	3.4	(1,056.5)
Changes in noncontrolling interest	17.6		17.6				(10.0)	7.6
Stock options and awards	130.2	1.2	127.8			1.2		130.2
Reacquired shares	(9.7)					(9.7)		(9.7)
Balance at Jun. 30, 2020	$ 5,855.2	$ 362.0	$ 6,155.0	$ 7,967.8	$ (1,989.7)	$ (6,639.9)	$ 35.0	$ 5,890.2