Restructuring - Narrative (Details) - Restructuring Plan, Impact of COVID-19 $ in Millions	1 Months Ended	3 Months Ended	6 Months Ended
	Mar. 31, 2020 employee	Jun. 30, 2020 USD ($)	Jun. 30, 2020 USD ($)
Employee Severance
Restructuring Cost and Reserve [Line Items]
Restructuring costs		$ 37	$ 37
Severance Costs		37
Employee Severance | Direct Vehicle and Operating
Restructuring Cost and Reserve [Line Items]
Restructuring costs		25	25
Employee Severance | Selling, General and Administrative Expenses
Restructuring Cost and Reserve [Line Items]
Restructuring costs		12	12
Employee Severance | Corporate, Non-Segment
Restructuring Cost and Reserve [Line Items]
Restructuring costs		3	3
Employee Severance | U.S. Rental Car
Restructuring Cost and Reserve [Line Items]
Restructuring costs		$ 34	$ 34
Other Restructuring
Restructuring Cost and Reserve [Line Items]
Number of positions eliminated | employee	20,000
Other Restructuring | U.S. Rental Car Segment and US Corporate Operations [Member]
Restructuring Cost and Reserve [Line Items]
Number of positions eliminated | employee	11,000