Capital Stock, Stock Awards, and Stock Options (Earnings Per Share) (Details 5) - 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
Schedule of Earnings Per Share, Basic and Diluted, Including Two Class Method [Line Items]
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
Less: Dividends paid–common stock outstanding and unvested restricted shares									(30,953)	(30,712)	(30,136)
Undistributed earnings									$ 174,335	$ 36,367	$ 321,939
Percent allocated to common stockholders									99.34%	99.43%	99.36%
Undistributed earnings allocated to common stockholders									$ 173,182	$ 36,160	$ 319,867
Add: Dividends paid–common stock outstanding									30,756	30,540	29,946
Numerator for basic earnings per share									203,938	66,700	349,813
Add: Additional undistributed earnings due to dilutive stock options									4	0	5
Numerator for diluted earnings per share									$ 203,942	$ 66,700	$ 349,818
Weighted average shares outstanding (shares)									4,639	4,823	4,951
Denominator for diluted earnings per share (shares)									4,654	4,836	4,965
Graham Holdings Company Common Stockholders:
Basic net income 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
Earnings Per Share, Diluted (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
Stock Option Plan [Member]
Schedule of Earnings Per Share, Basic and Diluted, Including Two Class Method [Line Items]
Add: Effect of dilutive stock options (shares)									15	13	14