Earnings Per Share (Details 1) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024
Numerator:
Net income attributable to Graham Holdings Company common stockholders	$ 23,894	$ 124,380
Less: Dividends paid-common stock outstanding and unvested restricted shares	(15,662)	(15,352)
Undistributed earnings	$ 8,232	$ 109,028
Percent allocated to common stockholders	99.38%	99.33%
Undistributed earnings allocated to common stockholders	$ 8,182	$ 108,295
Add: Dividends paid-common stock outstanding	15,563	15,250
Numerator for basic earnings per share	23,745	123,545
Add: Additional undistributed earnings due to dilutive stock options	0	4
Numerator for diluted earnings per share	$ 23,745	$ 123,549
Denominator:
Weighted average shares outstanding (shares)	4,320	4,432
Denominator for diluted earnings per share (shares)	4,358	4,457
Graham Holdings Company Common Stockholders:
Basic earnings per common share (in USD per share)	$ 5.50	$ 27.87
Diluted earnings per common share (in USD per share)	$ 5.45	$ 27.72
Stock Option Plan [Member]
Denominator:
Add: Effect of dilutive stock options (shares)	38	25