Fair Value Measurements (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total impairment charges	$ 19,029	$ 0
Goodwill impairment charge	976
Kaplan Languages Group (KLG) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total impairment charges	19,000
Goodwill impairment charge	1,000
Impairment charge related to the asset group held for sale	$ 18,000
Graham Holdings Company [Member] \| GHC One and GHC Two [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Guaranteed Return	8.00%
Percentage of Distributions Available to Common Unit Holders	80.00%
Group of Senior Managers of GHG [Member] \| GHC One and GHC Two [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Percentage of Distributions Available to Common Unit Holders	20.00%
Group of Senior Managers of GHG [Member] \| GHC One and GHC Two [Member] \| GHC One and GHC Two [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners	5.00%
Graham Holdings Company [Member] \| GHC One and GHC Two [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Percentage of Contributed Capital	95.00%
Group of Senior Managers of GHG [Member] \| GHC One and GHC Two [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Percentage of Contributed Capital	5.00%

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