Summary of Quarterly Operating Results (Unaudited) (Quarterly Results) (Details 1) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2023	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Operating Revenues
Operating Revenues	$ 1,166,813	$ 1,111,519	$ 1,104,999	$ 1,031,546	$ 1,064,032	$ 1,012,438	$ 933,302	$ 914,721	$ 4,414,877	$ 3,924,493	$ 3,185,974
Operating Costs and Expenses
Cost of services and goods	826,279	781,587	767,854	727,214	715,632	694,757	631,828	615,501
Other Operating Expenses	299,740	387,044	279,090	276,676	403,333	258,149	262,146	259,249
Selling, general and administrative									1,007,381	921,739	831,853
Depreciation of property, plant and equipment									86,064	73,297	71,415
Amortization of intangible assets									50,039	58,851	57,870
Impairment of goodwill and other long-lived assets									99,066	128,990	32,940
Costs and Expenses									4,345,484	3,840,595	3,108,599
Income (Loss) from Operations	40,794	(57,112)	58,055	27,656	(54,933)	59,532	39,328	39,971	69,393	83,898	77,375
Net Income (Loss)	55,690	(21,134)	124,171	52,977	6,643	33,840	(66,615)	96,566	211,704	70,434	353,327
Net income attributable to Graham Holdings Company common stockholders	$ 53,259	$ (23,031)	$ 122,788	$ 52,272	$ 6,160	$ 32,780	$ (67,485)	$ 95,624	205,288	67,079	352,075
Equity in (Losses) Earnings of Affiliates, Net									(5,183)	(2,837)	17,914
Interest income									7,122	3,226	3,409
Interest expense									(63,301)	(54,403)	(33,943)
Non-operating pension and postretirement benefit income, net									133,812	197,939	109,230
Gain (loss) on marketable equity securities, net									138,067	(139,589)	243,088
Other income (expense), net									19,094	33,500	32,554
Income (Loss) Before Income Taxes									299,004	121,734	449,627
Provision for (Benefit From) Income Taxes									87,300	51,300	96,300
Net Loss (Income) Attributable to Noncontrolling Interests									(6,416)	(3,355)	(1,252)
Quarterly Comprehensive (Loss) Income									$ 483,474	$ (568,158)	$ 720,149
Per Share Information Attributable to Graham Holdings Company Common Stockholders
Basic net income (loss) per common share (in usd per share)	$ 11.76	$ (5.02)	$ 25.96	$ 10.91	$ 1.28	$ 6.78	$ (13.95)	$ 19.50	$ 43.96	$ 13.83	$ 70.65
Basic average number of common shares outstanding (in shares)									4,639	4,823	4,951
Diluted net income per common share (in USD per share)	$ 11.72	$ (5.02)	$ 25.89	$ 10.88	$ 1.28	$ 6.76	$ (13.95)	$ 19.45	$ 43.82	$ 13.79	$ 70.45
Services [Member]
Operating Revenues
Operating Revenues									$ 2,484,327	$ 2,328,869	$ 2,089,800
Operating Costs and Expenses
Cost of services and goods									1,468,114	1,346,519	1,243,384
Goods [Member]
Operating Revenues
Operating Revenues									1,930,550	1,595,624	1,096,174
Operating Costs and Expenses
Cost of services and goods									$ 1,634,820	$ 1,311,199	$ 871,137