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Merger with Capella Education Company (Details) | 1 Months Ended |  |  |
--- | --- | --- | --- | ---
Oct. 31, 2017 | Mar. 31, 2018 shares | Dec. 31, 2017 shares | Dec. 31, 2016 shares
Common stock, shares authorized |  |  | 20,000,000 | 20,000,000
Merger Agreement |  |  |  |
Conversion ratio | 0.875 |  |  |
Voting equity interests (as a percentage) | 52.00% |  |  |
Forecast | Merger Agreement |  |  |  |
Common stock, shares authorized |  | 32,000,000 |  |
Capella | Merger Agreement |  |  |  |
Voting equity interests (as a percentage) | 48.00% |  |  |

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