Acquisitions and Dispositions (Narrative) (Details) In Millions, unless otherwise specified		3 Months Ended
Apr. 11, 2014 Common Class B [Member] Subsequent Event [Member] Sale of WPLG [Member]	Mar. 31, 2014 Kaplan [Member] business	Mar. 31, 2013 Other Businesses [Member] business
Business Acquisition [Line Items]
Number of businesses acquired		1	1
Number of shares received in Berkshire Hathaway agreement	1.6

Number of shares to be received from Berkshire Hathaway in exchange for WPLG, a number of Berkshire shares held by the Company and an amount of cash.

No definition available.

Name:	ghc_NumberofSharesReceivedinBerkshireHathawayAgreement
Namespace Prefix:	ghc_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant