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Accounting Policies (Narrative) (Details) $ in Thousands | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Aug. 31, 2017 USD ($) | Aug. 31, 2017 USD ($) warehouse | Aug. 31, 2016 USD ($) | Feb. 28, 2017 USD ($)
Accounting Policies [Abstract] |  |  |  |
Cash equivalents | $ 500 | $ 500 |  | $ 300
Restricted cash from collections on auto loan receivables | 404,276 | $ 404,276 |  | 380,353
Number of warehouse facilities | warehouse |  | 3 |  |
Required benchmark for account delinquency |  | 120 days |  |
Accumulated depreciation and amortization | 1,110,000 | $ 1,110,000 |  | 1,040,000
Restricted cash on deposit in reserve accounts | 55,800 | 55,800 |  | 52,800
Restricted investments | 75,200 | 75,200 |  | $ 70,800
Excess Tax Benefit from Share-based Compensation | $ 2,200 | $ 4,600 | $ 6,800 |

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