Other Non-Operating Income (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Education [Member] \| Higher Education [Member] \| Kaplan University Transaction [Member]
Schedule of Non-Operating Income (Expense) [Line Items]
Gain related to contingent consideration	$ 1.4	$ 1.3	$ 3.1	$ 2.8

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

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