Other Non-Operating Income (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Education [Member] \| Higher Education [Member] \| Kaplan University Transaction [Member]
Schedule of Non-Operating Income (Expense) [Line Items]
Gain related to contingent consideration	$ 0.8	$ 0.6	$ 1.7	$ 1.5

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

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