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1. Summary of Significant Accounting Policies (Details Narrative) - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Unrestricted cash balance	$ 12,731	$ 13,936	$ 19,322	$ 17,859
Other assets	$ 23,397	$ 30,252
Incremental shares excluded from EPS calculation	7,500	7,900	6,800
CPS Leasing, Inc. [Member]
Ownership percentage in subsidiary	80.00%
Repossessed Vehicles [Member]
Other assets	$ 9,700	$ 11,100
Dealer concentration [Member] \| Geographic Concentration [Member] \| TEXAS
Concentration percentage	7.40%	7.30%
Dealer concentration [Member] \| Geographic Concentration [Member] \| OHIO
Concentration percentage	7.40%	6.80%
Dealer concentration [Member] \| Geographic Concentration [Member] \| CALIFORNIA
Concentration percentage	7.10%	7.20%
Dealer concentration [Member] \| Geographic Concentration [Member] \| FLORIDA
Concentration percentage	5.90%	5.60%
Dealer concentration [Member] \| Geographic Concentration [Member] \| NORTH CAROLINA
Concentration percentage	5.80%	5.30%