Description Of Business, Ownership Formation, Basis Of Presentation, And Principles Of Consolidation Ownership (Details)	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2013 DriveTime Automotive Group, Inc [Member] Board of Directors Chairman [Member]	Dec. 31, 2012 DriveTime Automotive Group, Inc [Member] Board of Directors Chairman [Member]	Mar. 31, 2013 DriveTime Automotive Group, Inc [Member] Chief Executive Officer [Member]	Dec. 31, 2012 DriveTime Automotive Group, Inc [Member] Chief Executive Officer [Member]	Mar. 31, 2013 Variable Interest Entity, Primary Beneficiary [Member] Board of Directors Chairman [Member]	Dec. 31, 2012 Variable Interest Entity, Primary Beneficiary [Member] Board of Directors Chairman [Member]	Mar. 31, 2013 Variable Interest Entity, Primary Beneficiary [Member] Chief Executive Officer [Member]	Dec. 31, 2012 Variable Interest Entity, Primary Beneficiary [Member] Chief Executive Officer [Member]
Schedule of Company Ownership by Owner [Line Items]
Shares owned		100.0	100.0	1.8	1.8	100	100	1.8	1.8
Ownership percentage of company		98.30%	98.30%	1.70%	1.70%	98.30%	98.30%	1.70%	1.70%
DTAG loans as a percentage of loans DTAC is required to purchase	100.00%