Capital Stock, Stock Awards, and Stock Options (Earnings Per Share) (Details 5) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Schedule of Earnings Per Share, Basic and Diluted, Including Two Class Method [Line Items]
Net income attributable to Graham Holdings Company common stockholders	$ 352,075	$ 300,365	$ 327,855
Less: Dividends paid–common stock outstanding and unvested restricted shares	(30,136)	(29,970)	(29,553)
Undistributed earnings	$ 321,939	$ 270,395	$ 298,302
Percent allocated to common stockholders	99.36%	99.45%	99.45%
Undistributed earnings allocated to common stockholders	$ 319,867	$ 268,917	$ 296,665
Add: Dividends paid–common stock outstanding	29,946	29,812	29,387
Numerator for basic earnings per share	349,813	298,729	326,052
Add: Additional undistributed earnings due to dilutive stock options	5	4	13
Numerator for diluted earnings per share	$ 349,818	$ 298,733	$ 326,065
Weighted average shares outstanding (shares)	4,951	5,124	5,285
Denominator for diluted earnings per share (shares)	4,965	5,139	5,327
Graham Holdings Company Common Stockholders:
Basic net income per common share (in USD per share)	$ 70.65	$ 58.30	$ 61.70
Earnings Per Share, Diluted (in usd per share)	$ 70.45	$ 58.13	$ 61.21
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)	14	15	42