Income Taxes - Narrative (Details) - USD ($)		6 Months Ended
	Apr. 30, 2018	Jun. 30, 2018	Dec. 31, 2017	May 03, 2017
Income Tax Contingency [Line Items]
Uncertain tax positions		$ 0	$ 0
Related reserves		0	$ 0
Carvana Group
Income Tax Contingency [Line Items]
Gross deferred tax asset		68,700,000
Carvana Group | Class A Common Units
Income Tax Contingency [Line Items]
Gross deferred tax asset		$ 2,500,000
Investment owned, balance (in shares)	8,300,000			18,800,000
Exchange Agreement
Income Tax Contingency [Line Items]
Conversion of stock, converted (in shares)	6,900,000	12,000,000.0