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Fair value of of available-for-sale equity securities exchanged.

No definition available.

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Estimated fair value of business exchanged.

No definition available.

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This item represents the total realized gain included in earnings for the period as a result of exchanging marketable securities.

No definition available.

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Data Type:	xbrli:monetaryItemType
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Percent of noncontrolling interest purchased during the period.

No definition available.

Name:	ghc_NoncontrollingInterestPurchased
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Period Type:	duration

Number Berkshire shares exchanged held by Graham Holdings Company and an amount of cash in exchange for Graham Holdings Company common stock held by Berkshire Hathaway.

No definition available.

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Period Type:	instant

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.

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- Details

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Percentage of voting equity interests acquired at the acquisition date in the business combination.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount of gain (loss), before tax expense or benefit and not previously recognized, resulting from the sale of a business component.

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Name:	us-gaap_DiscontinuedOperationGainLossFromDisposalOfDiscontinuedOperationBeforeIncomeTax
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Amount of gain (loss), after tax expense or benefit and not previously recognized, resulting from the sale of a business component.

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

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-Subparagraph (SX 210.4-08.(h)(2))

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This item represents the total realized gain (loss) included in earnings for the period as a result of selling marketable securities categorized as trading, available-for-sale, or held-to-maturity. Additionally, this item would include any losses recognized for other than temporary impairments (OTTI) of the subject investments in debt and equity securities.

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The number of businesses acquired by the entity during the period.

No definition available.

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Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

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-Subparagraph (SX 210.3-04)

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