Contingent consideration gain related to the sale of a business.

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- Definition

Preferred annual return on portfolio investments guaranteed to the Company

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

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- Definition

Percentage of Contributed Capital

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- Definition

Percentage of distributions available to common unit holders

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- Definition

Amount of gain (loss) from sale and disposal of integrated set of activities and assets capable of being conducted and managed for purpose of providing return in form of dividend, lower cost, or other economic benefit to investor, owner, member and participant.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
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-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=109239629&loc=SL4582445-111684

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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- Definition

Change in noncontrolling interest during the period as a result of a change in the redemption value of redeemable noncontrolling interest.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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Acquisitions and Dispositions of Businesses (Dispositions and Other) (Narrative) (Details) $ in Thousands	1 Months Ended		3 Months Ended			6 Months Ended
	Nov. 30, 2019 business	Mar. 31, 2019 USD ($)	Jun. 30, 2020 USD ($)	Jun. 30, 2019 USD ($)	Mar. 31, 2019 USD ($)	Jun. 30, 2020 USD ($)	Jun. 30, 2019 USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain on sale of a business			$ 1,653	$ 232		$ 1,760	$ 421
Gain related to contingent consideration			$ 1,700			$ 1,800
Change in redemption value of mandatorily redeemable noncontrolling interest					$ (54)
Group of Senior Managers of GHG [Member] \| GHC One [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners			5.00%			5.00%
Percentage of Distributions Available to Common Unit Holders						20.00%
Graham Holdings Company [Member] \| GHC One [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Guaranteed Return						8.00%
Percentage of Distributions Available to Common Unit Holders						80.00%
Education [Member] \| Kaplan International [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of businesses disposed \| business	1
Hoover Treated Wood Products [Member] \| Manufacturing [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Change in redemption value of mandatorily redeemable noncontrolling interest		$ 600
Graham Holdings Company [Member] \| Hoover Treated Wood Products [Member] \| Manufacturing [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Ownership percentage by parent			98.00%			98.00%
Graham Holdings Company [Member] \| GHC One [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Percentage of Contributed Capital						95.00%
Group of Senior Managers of GHG [Member] \| GHC One [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Percentage of Contributed Capital						5.00%