Revenue from Contracts with Customers (Capitalized Contract Cost) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2023	Dec. 31, 2022
Revenue from Contract with Customer [Abstract]
Contract costs capitalized during the period	$ 16,068
Costs amortized during the period	(19,637)
Change in capitalized contract cost, other	541
Balance of costs to obtain a contract	$ 28,619	$ 31,647

Change in capitalized contract cost, other

No definition available.

Name:	ghc_ChangeinCapitalizedContractCostOther
Namespace Prefix:	ghc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Capitalized contract costs associated with new contracts entered into during the period.

+ References

No definition available.

+ Details

Name:	ghc_ContractCostsCapitalizedDuringthePeriod
Namespace Prefix:	ghc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of amortization expense for asset recognized from cost incurred to obtain or fulfill contract with customer.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 340
-SubTopic 40
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=126905575&loc=SL49131252-203054

+ Details

Name:	us-gaap_CapitalizedContractCostAmortization
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount, after accumulated amortization and accumulated impairment loss, of asset recognized from cost incurred to obtain or fulfill contract with customer.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 340
-SubTopic 40
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126905575&loc=SL49131252-203054

+ Details

Name:	us-gaap_CapitalizedContractCostNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration