Other Non-Operating Income (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Education [Member] \| Higher Education [Member] \| Kaplan University Transaction [Member]
Schedule of Non-Operating Income (Expense) [Line Items]
Gain related to contingent consideration	$ 0.9	$ 0.9

[Line Items] for Schedule of Non-Operating Income (Expense) [Table]

No definition available.

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