Revenue Recognition (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Revenues:
Re-rent revenue, Topic 842	$ 32	$ 34
Revenues	2,057	2,125
Topic 842
Revenues:
Revenues	1,518	1,637
Topic 606
Revenues:
Revenues	539	488
Equipment rentals
Revenues:
Revenues	1,667	1,783
Equipment rentals | Topic 842
Revenues:
Revenues	1,518	1,637
Equipment rentals | Topic 606
Revenues:
Revenues	149	146
Owned equipment rentals
Revenues:
Owned equipment rentals, Topic 842	1,405	1,522
Owned equipment rentals | Topic 842
Revenues:
Owned equipment rentals, Topic 842	1,405	1,522
Re-rent revenue
Revenues:
Re-rent revenue, Topic 842	32	34
Re-rent revenue | Topic 842
Revenues:
Re-rent revenue, Topic 842	32	34
Ancillary and Other Rental Revenues
Revenues:
Revenue from contract with customer	116	119
Other	114	108
Revenues	230	227
Ancillary and Other Rental Revenues | Topic 842
Revenues:
Revenue from contract with customer	0	0
Other	81	81
Revenues	81	81
Ancillary and Other Rental Revenues | Topic 606
Revenues:
Revenue from contract with customer	116	119
Other	33	27
Revenues	149	146
Sales of rental equipment
Revenues:
Revenue from contract with customer	267	208
Sales of rental equipment | Topic 606
Revenues:
Revenue from contract with customer	267	208
Sales of new equipment
Revenues:
Revenue from contract with customer	49	62
Sales of new equipment | Topic 606
Revenues:
Revenue from contract with customer	49	62
Contractor supplies sales
Revenues:
Revenue from contract with customer	24	25
Contractor supplies sales | Topic 606
Revenues:
Revenue from contract with customer	24	25
Service and other revenues
Revenues:
Revenue from contract with customer	50	47
Service and other revenues | Topic 606
Revenues:
Revenue from contract with customer	$ 50	$ 47