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Acquisitions and Dispositions of Businesses (Significant Component) (Details 3) - Kaplan University Transaction [Member] - Education [Member] - Higher Education [Member] - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2018 | Jun. 30, 2018
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |
Disposal Group, Not Discontinued Operation, Revenue | $ 0 | $ 91,526
Disposal Group, Not Discontinued Operation, Operating Income | $ 0 | $ 213

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