Related Party Transactions - Lease Agreements (Details) $ in Thousands		1 Months Ended						12 Months Ended
		Feb. 28, 2019 renewal_option	Nov. 30, 2018 renewal_option	Mar. 31, 2017 location renewal_option	Feb. 28, 2017 renewal_option	Dec. 31, 2016 renewal_option	Nov. 30, 2014 renewal_option location	Dec. 31, 2019 USD ($) renewal_option	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Related Party Transaction [Line Items]
Operating lease, number of renewal options (up to)								1
Purchase of certain leasehold improvements and equipment | $	[1]							$ 230,538	$ 143,668	$ 78,490
Related Party
Related Party Transaction [Line Items]
Purchase of certain leasehold improvements and equipment | $								$ 6,282
Maximum
Related Party Transaction [Line Items]
Operating leases, renewal term								20 years
DriveTime Automotive Group, Inc. | Building | Related Party | Lease Agreement for Fully-Operational Inspection and Reconditioning Center | Winder, Georgia
Related Party Transaction [Line Items]
Operating lease, number of renewal options (up to)					3
Operating leases, renewal term					5 years
Operating lease term					8 years
DriveTime Automotive Group, Inc. | Building | Related Party | Lease Agreement for Fully-Operational Inspection and Reconditioning Center | Cleveland, Ohio
Related Party Transaction [Line Items]
Operating lease term			3 years
DriveTime Automotive Group, Inc. | Building | Related Party | Related Party Lease Agreements
Related Party Transaction [Line Items]
Operating lease, cancellation terms, number of days prior written notice							60 days
Operating lease, number of renewal options (up to)				2			2
Operating leases, renewal term				1 year			1 year
Operating lease, renewal options, number of locations | location				10			10
Termination rights, prior written notice period				60 days
Operating lease term				12 months
DriveTime Automotive Group, Inc. | Building | Related Party | Related Party Lease Agreements | Cleveland, Ohio
Related Party Transaction [Line Items]
Operating lease, number of renewal options (up to)			3
Operating leases, renewal term			5 years
DriveTime Automotive Group, Inc. | Leasehold Improvements And Equipment | Related Party | Lease Agreement for Inspection and Reconditioning Center | Nashville, TN
Related Party Transaction [Line Items]
Operating lease, number of renewal options (up to)		3
Operating leases, renewal term		5 years
Operating lease term		4 years
Verde Investments, Inc. | Building | Related Party | Lease Agreement Related to Vehicle Inspection and Reconditioning Center | Tolleson, Arizona
Related Party Transaction [Line Items]
Operating lease, number of renewal options (up to)						4
Operating leases, renewal term						5 years
Verde Investments, Inc. | Building | Maximum | Related Party | Lease Agreement Related to Vehicle Inspection and Reconditioning Center | Tolleson, Arizona
Related Party Transaction [Line Items]
Operating lease term						15 years
Verde Investments, Inc. and DriveTime Automotive Group Inc. | Related Party | Related Party Lease Agreements
Related Party Transaction [Line Items]
Expenses from transactions with related party | $								$ 7,900	8,800	7,200
Verde Investments, Inc. and DriveTime Automotive Group Inc. | Related Party | Related Party Lease Agreements | Inventory
Related Party Transaction [Line Items]
Expenses from transactions with related party | $								3,300	4,400	2,800
Verde Investments, Inc. and DriveTime Automotive Group Inc. | Related Party | Related Party Lease Agreements | Selling, general and administrative
Related Party Transaction [Line Items]
Expenses from transactions with related party | $								$ 4,600	$ 4,400	$ 4,400

[1] A related party initially acquired $25.0 million of the senior unsecured notes during the year ended December 31, 2018, of which it subsequently disposed of $10.0 million, and held $15.0 million as of both December 31, 2019 and December 31, 2018.