Revenue Recognition (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Revenues:
Owned equipment rentals	$ 1,631	$ 1,367	$ 3,090	$ 2,533
Re-rent revenue	29	25	54	46
Ancillary and other rental revenues:
Delivery and pick-up	112	96	204	172
Other	84	67	161	127
Total ancillary and other rental revenues	196	163	365	299
Total equipment rentals	1,631	1,367	3,090	2,533
Service and other revenues	35	29	69	56
Total revenues	1,891	1,597	3,625	2,953
Topic 840
Revenues:
Re-rent revenue	29	25	54	46
Ancillary and other rental revenues:
Delivery and pick-up	0	0	0	0
Other	64	54	120	99
Total ancillary and other rental revenues	64	54	120	99
Total equipment rentals	1,499	1,258	2,845	2,333
Service and other revenues	0	0	0	0
Total revenues	1,499	1,258	2,845	2,333
Topic 606
Revenues:
Re-rent revenue	0		0
Ancillary and other rental revenues:
Delivery and pick-up	112		204
Other	20		41
Total ancillary and other rental revenues	132		245
Total equipment rentals	132		245
Service and other revenues	35		69
Total revenues	392		780
Topic 605
Revenues:
Re-rent revenue		0		0
Ancillary and other rental revenues:
Delivery and pick-up		96		172
Other		13		28
Total ancillary and other rental revenues		109		200
Total equipment rentals		109		200
Service and other revenues		29		56
Total revenues		339		620
Owned equipment rentals
Revenues:
Owned equipment rentals	1,406	1,179	2,671	2,188
Owned equipment rentals | Topic 840
Revenues:
Owned equipment rentals	1,406	1,179	2,671	2,188
Owned equipment rentals | Topic 606
Revenues:
Owned equipment rentals	0		0
Owned equipment rentals | Topic 605
Revenues:
Owned equipment rentals		0		0
Rental equipment
Ancillary and other rental revenues:
Sales revenue	157	133	338	239
Rental equipment | Topic 840
Ancillary and other rental revenues:
Sales revenue	0	0	0	0
Rental equipment | Topic 606
Ancillary and other rental revenues:
Sales revenue	157		338
Rental equipment | Topic 605
Ancillary and other rental revenues:
Sales revenue		133		239
New equipment
Ancillary and other rental revenues:
Sales revenue	44	47	86	86
New equipment | Topic 840
Ancillary and other rental revenues:
Sales revenue	0	0	0	0
New equipment | Topic 606
Ancillary and other rental revenues:
Sales revenue	44		86
New equipment | Topic 605
Ancillary and other rental revenues:
Sales revenue		47		86
Contractor supplies
Ancillary and other rental revenues:
Sales revenue	24	21	42	39
Contractor supplies | Topic 840
Ancillary and other rental revenues:
Sales revenue	0	0	0	0
Contractor supplies | Topic 606
Ancillary and other rental revenues:
Sales revenue	$ 24		$ 42
Contractor supplies | Topic 605
Ancillary and other rental revenues:
Sales revenue		$ 21		$ 39