Environmental and legal matters Environmental and legal matters (Details)	Jan. 27, 2020 USD ($)	Jul. 08, 2019	Mar. 03, 2017	Mar. 20, 2014
IRS investigation
Loss Contingencies
Number of facilities served search and seizure warrants			3
Individuals | CADE Investigation
Loss Contingencies
Number of Defendants				100
Current employee of MEG | CADE Investigation
Loss Contingencies
Number of Defendants				1
Defendant found liable, current employee of MEG | CADE Investigation
Loss Contingencies
Number of Defendants		1
Former employee of MEG | CADE Investigation
Loss Contingencies
Number of Defendants				2
Defendant found liable, former employee of MEG | CADE Investigation
Loss Contingencies
Number of Defendants		2
Companies | CADE Investigation
Loss Contingencies
Number of Defendants				18
Subsidiaries of Caterpillar Inc | CADE Investigation
Loss Contingencies
Number of Defendants				2
Subsequent Event | IBAMA allegations
Loss Contingencies
Proposed fine	$ 370,000