Condensed Consolidated Statements of Operations (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Income Statement [Abstract]
Operating Revenues	$ 738,820	$ 674,766	$ 2,168,621	$ 2,006,879
Operating Costs and Expenses [Abstract]
Operating	517,935	448,920	1,498,928	1,254,726
Selling, general and administrative	175,322	131,081	472,124	497,504
Depreciation of property, plant and equipment	15,351	13,648	42,758	41,909
Amortization of intangible assets	13,572	12,269	39,512	34,052
Impairment of long-lived assets	372	8,109	1,065	8,109
Total Operating Costs and Expenses	722,552	614,027	2,054,387	1,836,300
Income from Operations	16,268	60,739	114,234	170,579
Equity in earnings of affiliates, net	4,683	9,537	7,829	13,047
Interest income	1,474	611	4,753	3,884
Interest expense	(6,776)	(6,135)	(22,587)	(31,371)
Debt Extinguishment Costs	0	0	0	(11,378)
Non-operating pension and postretirement benefit income, net	19,556	22,214	51,737	66,641
Gain on marketable equity securities, net	17,404	44,962	49,261	28,306
Other income, net	5,556	3,142	36,135	14,662
Income Before Income Taxes	58,165	135,070	241,362	254,370
Provision for Income Taxes	15,200	10,000	59,500	39,700
Net Income	42,965	125,070	181,862	214,670
Net Loss (Income) Attributable to Noncontrolling Interests	180	(6)	112	(149)
Net Income Attributable to Graham Holdings Company Common Stockholders	$ 43,145	$ 125,064	$ 181,974	$ 214,521
Per Share Information Attributable to Graham Holdings Company Common Stockholders
Basic net income per common share in dollars per share	$ 8.12	$ 23.43	$ 34.24	$ 39.81
Basic average number of common shares outstanding in shares	5,285	5,302	5,285	5,354
Diluted net income per common share in dollars per share	$ 8.05	$ 23.28	$ 33.96	$ 39.54
Diluted average number of common shares outstanding in shares	5,329	5,337	5,328	5,390