Income Taxes - Narrative (Details) - USD ($) shares in Millions		3 Months Ended		9 Months Ended
	Apr. 12, 2018	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	May 21, 2020
Income Tax Contingency [Line Items]
Uncertain tax positions		$ 0		$ 0		$ 0
Related reserves		$ 0		$ 0		$ 0
Effective income tax rate, expense (benefit)		0.30%	0.40%	0.20%	(0.10%)
Car360
Income Tax Contingency [Line Items]
Deferred tax liability	$ 2,000,000
Deferred tax liability, amortization expense (less than)		$ 1,000,000	$ 1,000,000	$ 1,000,000	$ 1,000,000
Car360 | Minimum
Income Tax Contingency [Line Items]
Deferred tax liability, amortization period	5 years
Car360 | Maximum
Income Tax Contingency [Line Items]
Deferred tax liability, amortization period	7 years
Carvana Group
Income Tax Contingency [Line Items]
Gross deferred tax asset, acquired during period		$ 199,000,000	$ 47,000,000	$ 641,000,000	$ 56,000,000
Carvana Group | Class A Units | Public Equity Offering
Income Tax Contingency [Line Items]
LLC units purchased (in shares)			23.0		23.0		6.3
Gross deferred tax asset, purchased during period			$ 14,000,000		$ 14,000,000
Exchange Agreement
Income Tax Contingency [Line Items]
LLC units acquired (in shares)		3.0		11.0	2.0
Exchange Agreement | Class A Units
Income Tax Contingency [Line Items]
LLC units acquired (in shares)		3.0	1.0	11.0	2.0