Restructuring (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Restructuring details
Restructuring and related expected costs	$ 67		$ 67
Restructuring costs	37	$ 4	62	$ 29
Restructuring reserve
Beginning balance			24
Charges incurred			62
Cash payments			(21)
Other non-cash changes			(31)
Ending balance	34		34
U.S. Rental Car
Restructuring details
Restructuring costs	30	2	51	18
International Rental Car
Restructuring details
Restructuring costs	3	4	7	11
Corporate
Restructuring details
Restructuring costs	4	(2)	4	0
Direct vehicle and operating
Restructuring details
Restructuring costs	29	0	38	15
Selling, general and administrative
Restructuring details
Restructuring costs	8	4	24	14
Termination benefits
Restructuring details
Restructuring costs	7	4	23	16
Restructuring reserve
Beginning balance			9
Charges incurred			23
Cash payments			(15)
Other non-cash changes			0
Ending balance	17		17
Impairments and asset write-downs
Restructuring details
Restructuring costs	28	1	31	2
Facility closure and lease obligation costs
Restructuring details
Restructuring costs	2	1	7	15
Other
Restructuring details
Restructuring costs	0	$ (2)	1	$ (4)
Restructuring reserve
Beginning balance			15
Charges incurred			39
Cash payments			(6)
Other non-cash changes			(31)
Ending balance	$ 17		$ 17