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Total loss recognized during the period from the impairment of goodwill plus the loss recognized in the period resulting from the impairment of the carrying amount of intangible assets, other than goodwill.

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The charge against earnings resulting from the write down of long lived assets other than goodwill due to the difference between the carrying value and lower fair value.

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Fair Value Measurements (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impairment of intangible and other long-lived assets	$ 2,235		$ 2,235
Impairment of goodwill and intangible assets				$ 26,287
Impairment of cost method investments	1,486	$ 0	14,165	744
Gain on cost method investments	$ 0	191	$ 0	$ 191
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%		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%
N2K Networks [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impairment on equity method investment		$ 14,400