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	296.5			296.5			3.9	300.4
Comprehensive income (loss) activity	88.0				88.0		0.9	88.9
Cash dividends declared	(132.6)			(132.6)			(9.0)	(141.6)
Stock options and awards	99.8	1.2	97.8			0.8		99.8
Reacquired shares	(131.4)					(131.4)		(131.4)
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
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
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	283.4			283.4			6.8	290.2
Comprehensive income (loss) activity	(24.0)				(24.0)		0.5	(23.5)
Cash dividends declared	(135.9)			(135.9)			(10.0)	(145.9)
Changes in noncontrolling interest							0.7	0.7
Stock options and awards	112.6	1.2	111.0			0.4		112.6
Reacquired shares	(95.0)					(95.0)		(95.0)
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