Consolidated Statements of Operations (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended									12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013		Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Operating Revenues
Education	$ 551,381	$ 543,918	$ 542,964	$ 522,154	$ 550,618	$ 543,599		$ 544,878	$ 524,639	$ 2,160,417	$ 2,163,734	$ 2,184,532
Subscriber	184,035	183,161	187,723	191,128	186,297	190,302		192,273	186,790	746,047	755,662	732,370
Advertising	101,271	81,583	82,475	78,247	87,692	73,549		79,898	69,122	343,576	310,261	337,621
Other	88,656	90,209	61,249	45,012	42,635	48,651	[1]	50,103	36,865	285,126	178,254	118,063
Total Operating Revenues	925,343	898,871	874,411	836,541	867,242	856,101		867,152	817,416	3,535,166	3,407,911	3,372,586
Operating Costs and Expenses
Operating	391,348	398,922	395,627	376,463	372,471	393,010	[1]	392,500	374,516	1,562,360	1,532,497	1,535,237
Selling, general and administrative	319,854	358,189	322,240	325,275	331,814	327,062		318,731	333,894	1,325,558	1,311,501	1,317,494
Depreciation of property, plant and equipment	45,366	53,074	51,989	53,217	58,924	54,672		56,849	58,910	203,646	229,355	240,139
Amortization of intangible assets	5,251	7,405	2,995	2,717	3,359	2,468		2,950	3,362	18,368	12,139	19,510
Impairment of goodwill and other long-lived assets										17,302	3,250	111,593
Total Operating Costs and Expenses	779,121	817,590	772,851	757,672	769,818	777,212		771,030	770,682	3,127,234	3,088,742	3,223,973
Income from Operations	146,222	81,281	101,560	78,869	97,424	78,889		96,122	46,734	407,932	319,169	148,613
Equity in earnings of affiliates, net	202	4,613	91,503	4,052	37	5,892		3,868	3,418	100,370	13,215	14,086
Interest income	367	529	641	599	590	642		522	510	2,136	2,264	3,393
Interest expense	(9,879)	(9,330)	(8,557)	(8,820)	(8,838)	(9,221)		(9,048)	(8,960)	(36,586)	(36,067)	(35,944)
Other income (expense), net	387,346	64,526	268,114	133,273	(14,920)	8,110		(12,858)	(4,083)	853,259	(23,751)	(5,456)
Income from Continuing Operations Before Income Taxes	524,258	141,619	453,261	207,973	74,293	84,312		78,606	37,619	1,327,111	274,830	124,692
Provision for Income Taxes	191,900	58,200	78,600	77,400	24,100	29,900		31,700	15,800	406,100	101,500	73,400
Income from Continuing Operations	332,358	83,419	374,661	130,573	50,193	54,412		46,906	21,819	921,011	173,330	51,292
Income from Discontinued Operations, Net of Tax	2,308	(6,980)	375,189	1,732	106,335	(23,988)		(1,772)	(16,560)	372,249	64,015	80,895
Net Income	334,666	76,439	749,850	132,305	156,528	30,424		45,134	5,259	1,293,260	237,345	132,187
Net Loss (Income) Attributable to Noncontrolling Interests	(256)	121	499	219	(55)	(75)		(253)	(97)	583	(480)	(74)
Net Income Attributable to Graham Holdings Company	334,410	76,560	750,349	132,524	156,473	30,349		44,881	5,162	1,293,843	236,865	132,113
Redeemable Preferred Stock Dividends	0	(209)	(212)	(426)	0	(205)		(206)	(444)	(847)	(855)	(895)
Net Income Attributable to Graham Holdings Company Common Stockholders	334,410	76,351	750,137	132,098	156,473	30,144		44,675	4,718	1,292,996	236,010	131,218
Amounts Attributable to Graham Holdings Company Common Stockholders
Income from continuing operations	332,102	83,331	374,948	130,366	50,138	54,132		46,447	21,278	920,747	171,995	50,323
Income from Discontinued Operations, Net of Tax	2,308	(6,980)	375,189	1,732	106,335	(23,988)		(1,772)	(16,560)	372,249	64,015	80,895
Net income attributable to Graham Holdings Company common stockholders	$ 334,410	$ 76,351	$ 750,137	$ 132,098	$ 156,473	$ 30,144		$ 44,675	$ 4,718	$ 1,292,996	$ 236,010	$ 131,218
Per Share Information Attributable to Graham Holdings Company Common Stockholders
Basic income per common share from continuing operations in dollars per share	$ 57.31	$ 14.38	$ 50.39	$ 17.62	$ 6.79	$ 7.29		$ 6.26	$ 2.87	$ 139.44	$ 23.39	$ 6.40
Basic income per common share from discontinued operations in dollars per share	$ 0.40	$ (1.20)	$ 50.41	$ 0.23	$ 14.41	$ (3.22)		$ (0.24)	$ (2.23)	$ 56.37	$ 8.71	$ 10.99
Basic net income per common share in dollars per share	$ 57.71	$ 13.18	$ 100.80	$ 17.85	$ 21.20	$ 4.07		$ 6.02	$ 0.64	$ 195.81	$ 32.10	$ 17.39
Basic average number of common shares outstanding in shares	5,678	5,671	7,284	7,275	7,266	7,231		7,229	7,227	6,470	7,238	7,360
Diluted income per common share from continuing operations in dollars per share	$ 57.01	$ 14.32	$ 50.22	$ 17.56	$ 6.77	$ 7.28		$ 6.26	$ 2.87	$ 138.88	$ 23.36	$ 6.40
Diluted income per common share from discontinued operations in dollars per share	$ 0.40	$ (1.20)	$ 50.26	$ 0.23	$ 14.37	$ (3.23)		$ (0.24)	$ (2.23)	$ 56.15	$ 8.69	$ 10.99
Diluted net income per common share in dollars per share	$ 57.41	$ 13.12	$ 100.48	$ 17.79	$ 21.14	$ 4.05		$ 6.02	$ 0.64	$ 195.03	$ 32.05	$ 17.39
Diluted average number of common shares outstanding in shares	5,770	5,757	7,363	7,352	7,347	7,337		7,283	7,266	6,559	7,333	7,404

[1] Other revenue and operating expenses of $29.9 million from the third quarter of 2013 have been revised to correctly present revenue on a net basis for certain third quarter contracts that were previously reported on a gross basis. The amounts did not impact net income, and the Company concluded that the amounts were not material to the Company’s consolidated financial statements.