SPECIAL (GAINS) AND CHARGES - Restructuring and Non-Restructuring Activity (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Restructuring
Recorded expense	$ 6.4		$ 241.2
Net cash payments	(23.2)		(127.8)
Non-cash charges			(8.4)
Effect of foreign currency translation			(1.0)
Restructuring liability	87.2		104.0
Other restructuring information
Special (gains) and charges	52.4	$ 40.3
Other special gains and charges	5.7
Non-restructuring Special (Gains) and Charges
Property, Plant and Equipment, Net	3,920.7		3,954.9
Special (gains) and charges
Other restructuring information
Restructuring charges incurred, pre-tax	4.3	37.1
ChampionX Separation	36.6	4.3
ChampionX Separation, after tax	31.8	3.3
Special (gains) and charges	52.4	40.3
Business combination advisory and legal fees, pre tax	5.4	2.5
Business combination advisory and legal fees, after tax	3.6	1.8
Other special gains and charges	6.1	(3.6)
Other special gains and charges, after-tax	4.6	(4.3)
Cost of sales
Other restructuring information
Restructuring charges incurred, pre-tax	3.0	3.4
Special (gains) and charges	9.1	3.6
Business combination advisory and legal fees, pre tax	0.4	0.2
Interest expense
Other restructuring information
Special (gains) and charges	0.2	0.2
Business combination advisory and legal fees, pre tax		0.2
Business combination advisory and legal fees, after tax		0.1
Employee termination costs
Restructuring
Recorded expense	4.3		216.1
Net cash payments	(22.1)		(112.6)
Effect of foreign currency translation			(1.0)
Restructuring liability	84.7		102.5
Asset disposals
Restructuring
Recorded expense			5.2
Net cash payments			1.2
Non-cash charges			(6.4)
Other
Restructuring
Recorded expense	2.1		19.9
Net cash payments	(1.1)		(16.4)
Non-cash charges			(2.0)
Restructuring liability	2.5		1.5
Product and sold equipment | Cost of sales
Other restructuring information
Special (gains) and charges	9.1	3.6
Business combination advisory and legal fees, pre tax	0.4	0.2
Business combination advisory and legal fees, after tax	0.3	$ 0.1
Other special gains and charges	5.7
Other special gains and charges, after-tax	3.8
2018 Restructuring Plan
Other restructuring information
Restructuring charge expected to be incurred, pre-tax	260.0
Restructuring charge expected to be incurred, after tax	200.0
2018 Restructuring Plan | Special (gains) and charges
Restructuring
Restructuring liability	87.2
Other restructuring information
Restructuring charges incurred to date, pre-tax	247.6
Restructuring charges incurred to date, after-tax	189.4
Restructuring charges incurred, pre-tax	6.4
Restructuring charges incurred, after tax	5.4
Immaterial Restructuring Plan
Other restructuring information
Restructuring charges incurred, pre-tax	0.9
Restructuring charges incurred, after tax	0.7
Prior Year Plans
Restructuring
Cash payments	(0.4)
Restructuring liability	7.4		$ 7.7
Other restructuring information
Cash payments	$ 0.4