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Cancellation Reserves (Tables) | 9 Months Ended
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Nov. 30, 2016
Cancellation Reserves [Abstract] |
Schedule Of Cancellation Reserves Accrual | Cancellation Reserves
| Three Months Ended November 30 |  | Nine Months Ended November 30
(In millions) | 2016 |  | 2015 |  | 2016 |  | 2015
Balance as of beginning of period | $ | 113.3 |  |  | $ | 108.1 |  |  | $ | 110.2 |  |  | $ | 94.4 |
Cancellations | (16.8 | ) |  | (16.9 | ) |  | (49.6 | ) |  | (45.6 | )
Provision for future cancellations | 15.9 |  |  | 18.6 |  |  | 51.8 |  |  | 61.0 |
Balance as of end of period | $ | 112.4 |  |  | $ | 109.8 |  |  | $ | 112.4 |  |  | $ | 109.8 |

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- Definition Contract Cancellation Reserve [Table Text Block] + References No definition available. + Details
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- Definition Contract Cancellation Reserves [Abstract] + References No definition available. + Details
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Namespace Prefix: | kmx_
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