Cummins Inc. Annual report pursuant to Section 13 and 15(d)

REVENUE RECOGNITION LONG-TERM CONTRACTS AND DEFERRED AND UNBILLED REVENUE REVENUE RECOGNITION LONG-TERM CONTRATS AND DEFERRED AND UNBILLED REVENUE (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Revenue from Contract with Customer [Abstract]
Revenue, Remaining Performance Obligation, Amount	$ 879
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Unbilled revenue	114	$ 68
Deferred revenue, primarily extended warranty	1,531	1,354
Contract with Customer, Liability, Revenue Recognized	372	$ 365
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01
Revenue from Contract with Customer [Abstract]
Revenue, Remaining Performance Obligation, Amount	$ 160
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	12 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01
Revenue from Contract with Customer [Abstract]
Revenue, Remaining Performance Obligation, Amount	$ 719
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	10 years