$GHC
Graham Holdings Co Stock $ghc

$ghc Overview Financials Valuation SEC Filings Company Website

2019 Q4 Form 10-K Financial Statement

#000010488920000007 Filed on February 26, 2020

Income Statement

Concept	2019 Q4	2019 Q1	2019
Revenue	$763.5M	$692.2M	$2.932B
YoY Change	10.8%	4.97%	8.76%
Cost Of Revenue	$524.3M	$477.2M	$2.023B
YoY Change	21.17%	30.67%	19.9%
Gross Profit	$239.2M	$215.0M	$908.9M
YoY Change	-6.71%	-26.95%	-9.88%
Gross Profit Margin	31.33%	31.06%	31.0%
Selling, General & Admin	$170.6M	$148.4M	$642.7M
YoY Change	11.8%	-34.06%	-1.14%
% of Gross Profit	71.32%	69.02%	70.71%
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$16.50M	$26.58M	$59.25M
YoY Change	11.35%	6.22%	4.46%
% of Gross Profit	6.9%	12.36%	6.52%
Operating Expenses	$200.8M	$175.0M	$755.2M
YoY Change	11.06%	-22.24%	0.12%
Operating Profit	$30.31M	$40.00M	$144.5M
YoY Change	-59.9%	-9.52%	-41.28%
Interest Expense	$7.192M	$7.425M	$29.78M
YoY Change	10.12%	-8.0%	-21.43%
% of Operating Profit	23.73%	18.56%	20.6%
Other Income/Expense, Net	-$3.704M	$29.35M	$32.43M
YoY Change	-70.51%	219.48%	1442.13%
Pretax Income	$185.1M	$109.3M	$426.5M
YoY Change	167.75%	93.23%	31.83%
Income Tax	$39.10M	$27.60M	$98.60M
% Of Pretax Income	21.12%	25.25%	23.12%
Net Earnings	$145.9M	$81.75M	$327.9M
YoY Change	157.35%	90.59%	20.89%
Net Earnings / Revenue	19.11%	11.81%	11.18%
Basic Earnings Per Share	$27.45	$15.38	$61.70
Diluted Earnings Per Share	$27.25	$15.26	$61.21
COMMON SHARES
Basic Shares Outstanding	5.284M shares	5.284M shares	5.285M shares
Diluted Shares Outstanding		5.326M shares	5.327M shares

Balance Sheet

Concept	2019 Q4	2019 Q1	2019
SHORT-TERM ASSETS
Cash & Short-Term Investments	$800.1M	$698.8M	$800.1M
YoY Change	4.21%	-13.43%	4.21%
Cash & Equivalents	$200.2M	$170.9M	$200.2M
Short-Term Investments	$600.0M	$527.9M	$600.0M
Other Short-Term Assets	$1.400M	$77.13M	$119.5M
YoY Change	-98.31%	6.24%	27.67%
Inventory	$108.9M	$107.3M	$108.9M
Prepaid Expenses	$92.29M
Receivables	$595.3M	$503.8M	$595.3M
Other Receivables	$39.70M	$50.40M	$39.70M
Total Short-Term Assets	$1.663B	$1.478B	$1.664B
YoY Change	8.56%	-2.89%	8.56%
LONG-TERM ASSETS
Property, Plant & Equipment	$384.7M	$319.4M	$911.1M
YoY Change	31.25%	23.47%	210.85%
Goodwill	$1.388B	$1.340B
YoY Change	6.98%	2.95%
Intangibles
YoY Change
Long-Term Investments	$162.2M	$140.1M	$162.2M
YoY Change	12.8%	6.22%	12.8%
Other Assets	$128.5M	$129.3M	$1.433B
YoY Change	9.04%	4.58%	26.23%
Total Long-Term Assets	$4.268B	$3.720B	$4.268B
YoY Change	32.06%	14.82%	32.06%
TOTAL ASSETS
Total Short-Term Assets	$1.663B	$1.478B	$1.664B
Total Long-Term Assets	$4.268B	$3.720B	$4.268B
Total Assets	$5.931B	$5.197B	$5.931B
YoY Change	24.5%	9.16%	24.5%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$507.7M	$422.4M	$367.0M
YoY Change	4.34%	-3.01%	8.87%
Accrued Expenses	$92.70M	$82.40M	$233.5M
YoY Change			56.19%
Deferred Revenue
YoY Change
Short-Term Debt	$0.00	$0.00	$0.00
YoY Change
Long-Term Debt Due	$82.18M	$9.600M	$82.20M
YoY Change	1184.05%	-97.64%	1184.38%
Total Short-Term Liabilities	$1.042B	$829.8M	$1.042B
YoY Change	28.28%	-28.01%	28.28%
LONG-TERM LIABILITIES
Long-Term Debt	$430.7M	$500.2M	$431.5M
YoY Change	-8.52%	449.24%	-8.35%
Other Long-Term Liabilities	$27.22M	$17.40M	$698.1M
YoY Change	-52.98%	-72.69%	193.81%
Total Long-Term Liabilities	$457.9M	$517.6M	$1.130B
YoY Change	-13.39%	234.41%	59.46%
TOTAL LIABILITIES
Total Short-Term Liabilities	$1.042B	$829.8M	$1.042B
Total Long-Term Liabilities	$457.9M	$517.6M	$1.130B
Total Liabilities	$2.599B	$2.194B	$2.612B
YoY Change	41.02%	17.23%	41.4%
SHAREHOLDERS EQUITY
Retained Earnings	$6.534B	$6.303B
YoY Change	4.78%	8.7%
Common Stock	$20.00M	$20.00M
YoY Change	0.0%	0.0%
Preferred Stock
YoY Change
Treasury Stock (at cost)	$3.920B	$3.918B
YoY Change	-0.05%	0.94%
Treasury Stock Shares
Shareholders Equity	$3.319B	$2.994B	$3.319B
YoY Change
Total Liabilities & Shareholders Equity	$5.931B	$5.197B	$5.931B
YoY Change	24.5%	9.16%	24.5%

Cashflow Statement

Concept	2019 Q4	2019 Q1	2019
OPERATING ACTIVITIES
Net Income	$145.9M	$81.75M	$327.9M
YoY Change	157.35%	90.59%	20.89%
Depreciation, Depletion And Amortization	$16.50M	$26.58M	$59.25M
YoY Change	11.35%	6.22%	4.46%
Cash From Operating Activities	$92.90M	-$37.92M	$165.2M
YoY Change	-2.31%	-300.11%	-42.46%
INVESTING ACTIVITIES
Capital Expenditures	-$17.80M	$28.25M	$93.50M
YoY Change	-54.71%	61.38%	-4.77%
Acquisitions		$83.72M	$179.4M
YoY Change		3096.68%	60.85%
Other Investing Activities	-$16.50M	-$45.60M	-$920.0K
YoY Change	-59.16%	-860.0%
Cash From Investing Activities	-$34.20M	-$73.88M	-$236.7M
YoY Change	-57.09%	540.75%	2.5%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net		$0.00	$2.103M
YoY Change		-100.0%	-98.22%
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	-6.900M	$37.03M	$18.73M
YoY Change	-72.62%	-140.71%	-109.74%
NET CHANGE
Cash From Operating Activities	92.90M	-$37.92M	$165.2M
Cash From Investing Activities	-34.20M	-$73.88M	-$236.7M
Cash From Financing Activities	-6.900M	$37.03M	$18.73M
Net Change In Cash	51.80M	-$72.99M	-$50.07M
YoY Change	-628.57%	-8.05%	-65.1%
FREE CASH FLOW
Cash From Operating Activities	$92.90M	-$37.92M	$165.2M
Capital Expenditures	-$17.80M	$28.25M	$93.50M
Free Cash Flow	$110.7M	-$66.17M	$71.66M
YoY Change	-17.63%	-4679.52%	-62.05%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
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CY2019	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
CY2019	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
CY2019	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2019
CY2019	dei	Entity Central Index Key EntityCentralIndexKey	0000104889
CY2018Q2	ghc	Debt Extinguishment Costs Netof Tax DebtExtinguishmentCostsNetofTax	-8600000	USD
CY2018	ghc	Debt Extinguishment Costs Netof Tax DebtExtinguishmentCostsNetofTax	-8600000	USD
CY2018Q3	ghc	Discrete Deferred Tax Benefit DiscreteDeferredTaxBenefit	17800000	USD
CY2018	ghc	Discrete Deferred Tax Benefit DiscreteDeferredTaxBenefit	17800000	USD
CY2018Q1	ghc	Foreign Currency Transaction Gain Loss Unrealized Netof Tax ForeignCurrencyTransactionGainLossUnrealizedNetofTax	100000	USD
CY2018Q2	ghc	Foreign Currency Transaction Gain Loss Unrealized Netof Tax ForeignCurrencyTransactionGainLossUnrealizedNetofTax	-1700000	USD
CY2018Q3	ghc	Foreign Currency Transaction Gain Loss Unrealized Netof Tax ForeignCurrencyTransactionGainLossUnrealizedNetofTax	-100000	USD
CY2018Q4	ghc	Foreign Currency Transaction Gain Loss Unrealized Netof Tax ForeignCurrencyTransactionGainLossUnrealizedNetofTax	-1200000	USD
CY2018	ghc	Foreign Currency Transaction Gain Loss Unrealized Netof Tax ForeignCurrencyTransactionGainLossUnrealizedNetofTax	-2900000	USD
CY2019Q1	ghc	Foreign Currency Transaction Gain Loss Unrealized Netof Tax ForeignCurrencyTransactionGainLossUnrealizedNetofTax	400000	USD
CY2019Q2	ghc	Foreign Currency Transaction Gain Loss Unrealized Netof Tax ForeignCurrencyTransactionGainLossUnrealizedNetofTax	100000	USD
CY2019Q3	ghc	Foreign Currency Transaction Gain Loss Unrealized Netof Tax ForeignCurrencyTransactionGainLossUnrealizedNetofTax	500000	USD
CY2019Q4	ghc	Foreign Currency Transaction Gain Loss Unrealized Netof Tax ForeignCurrencyTransactionGainLossUnrealizedNetofTax	-1800000	USD
CY2019	ghc	Foreign Currency Transaction Gain Loss Unrealized Netof Tax ForeignCurrencyTransactionGainLossUnrealizedNetofTax	-800000	USD
CY2018Q1	ghc	Gain Loss On Marketable Equity Securities Netof Tax GainLossOnMarketableEquitySecuritiesNetofTax	-10700000	USD
CY2018Q2	ghc	Gain Loss On Marketable Equity Securities Netof Tax GainLossOnMarketableEquitySecuritiesNetofTax	-1900000	USD
CY2018Q3	ghc	Gain Loss On Marketable Equity Securities Netof Tax GainLossOnMarketableEquitySecuritiesNetofTax	33600000	USD
CY2018Q4	ghc	Gain Loss On Marketable Equity Securities Netof Tax GainLossOnMarketableEquitySecuritiesNetofTax	-33600000	USD
CY2018	ghc	Gain Loss On Marketable Equity Securities Netof Tax GainLossOnMarketableEquitySecuritiesNetofTax	-12600000	USD
CY2019Q1	ghc	Gain Loss On Marketable Equity Securities Netof Tax GainLossOnMarketableEquitySecuritiesNetofTax	18100000	USD
CY2019Q2	ghc	Gain Loss On Marketable Equity Securities Netof Tax GainLossOnMarketableEquitySecuritiesNetofTax	5800000	USD
CY2019Q3	ghc	Gain Loss On Marketable Equity Securities Netof Tax GainLossOnMarketableEquitySecuritiesNetofTax	13100000	USD
CY2019Q4	ghc	Gain Loss On Marketable Equity Securities Netof Tax GainLossOnMarketableEquitySecuritiesNetofTax	37100000	USD
CY2019	ghc	Gain Loss On Marketable Equity Securities Netof Tax GainLossOnMarketableEquitySecuritiesNetofTax	74000000	USD
CY2018Q4	ghc	Gain On Lump Sum Pension Settlement And Curtailment Of Postretirement Benefit Plans Netof Tax GainOnLumpSumPensionSettlementAndCurtailmentOfPostretirementBenefitPlansNetofTax	22200000	USD
CY2018	ghc	Gain On Lump Sum Pension Settlement And Curtailment Of Postretirement Benefit Plans Netof Tax GainOnLumpSumPensionSettlementAndCurtailmentOfPostretirementBenefitPlansNetofTax	22200000	USD
CY2019Q1	ghc	Gainon Saleof Gimlet Media After Tax GainonSaleofGimletMediaAfterTax	21700000	USD
CY2019	ghc	Gainon Saleof Gimlet Media After Tax GainonSaleofGimletMediaAfterTax	21700000	USD
CY2018Q1	ghc	Non Operating Gain From Sales Writeups And Impairments Of Investments And Related To Sales Of Land And Businesses Including Losses On Guarantor Obligations Netof Tax NonOperatingGainFromSalesWriteupsAndImpairmentsOfInvestmentsAndRelatedToSalesOfLandAndBusinessesIncludingLossesOnGuarantorObligationsNetofTax	3600000	USD
CY2018Q2	ghc	Non Operating Gain From Sales Writeups And Impairments Of Investments And Related To Sales Of Land And Businesses Including Losses On Guarantor Obligations Netof Tax NonOperatingGainFromSalesWriteupsAndImpairmentsOfInvestmentsAndRelatedToSalesOfLandAndBusinessesIncludingLossesOnGuarantorObligationsNetofTax	1800000	USD
CY2018Q3	ghc	Non Operating Gain From Sales Writeups And Impairments Of Investments And Related To Sales Of Land And Businesses Including Losses On Guarantor Obligations Netof Tax NonOperatingGainFromSalesWriteupsAndImpairmentsOfInvestmentsAndRelatedToSalesOfLandAndBusinessesIncludingLossesOnGuarantorObligationsNetofTax	8000000	USD
CY2018Q4	ghc	Non Operating Gain From Sales Writeups And Impairments Of Investments And Related To Sales Of Land And Businesses Including Losses On Guarantor Obligations Netof Tax NonOperatingGainFromSalesWriteupsAndImpairmentsOfInvestmentsAndRelatedToSalesOfLandAndBusinessesIncludingLossesOnGuarantorObligationsNetofTax	-7700000	USD
CY2018	ghc	Non Operating Gain From Sales Writeups And Impairments Of Investments And Related To Sales Of Land And Businesses Including Losses On Guarantor Obligations Netof Tax NonOperatingGainFromSalesWriteupsAndImpairmentsOfInvestmentsAndRelatedToSalesOfLandAndBusinessesIncludingLossesOnGuarantorObligationsNetofTax	5700000	USD
CY2018Q1	ghc	Reductionto Operating Expenses In Association With Spectrum Repack Mandate Netof Tax ReductiontoOperatingExpensesInAssociationWithSpectrumRepackMandateNetofTax	200000	USD
CY2018Q2	ghc	Reductionto Operating Expenses In Association With Spectrum Repack Mandate Netof Tax ReductiontoOperatingExpensesInAssociationWithSpectrumRepackMandateNetofTax	600000	USD
CY2018Q3	ghc	Reductionto Operating Expenses In Association With Spectrum Repack Mandate Netof Tax ReductiontoOperatingExpensesInAssociationWithSpectrumRepackMandateNetofTax	800000	USD
CY2018Q4	ghc	Reductionto Operating Expenses In Association With Spectrum Repack Mandate Netof Tax ReductiontoOperatingExpensesInAssociationWithSpectrumRepackMandateNetofTax	1400000	USD
CY2018	ghc	Reductionto Operating Expenses In Association With Spectrum Repack Mandate Netof Tax ReductiontoOperatingExpensesInAssociationWithSpectrumRepackMandateNetofTax	3000000	USD
CY2019Q1	ghc	Reductionto Operating Expenses In Association With Spectrum Repack Mandate Netof Tax ReductiontoOperatingExpensesInAssociationWithSpectrumRepackMandateNetofTax	1400000	USD
CY2019Q2	ghc	Reductionto Operating Expenses In Association With Spectrum Repack Mandate Netof Tax ReductiontoOperatingExpensesInAssociationWithSpectrumRepackMandateNetofTax	6000000	USD
CY2019Q3	ghc	Reductionto Operating Expenses In Association With Spectrum Repack Mandate Netof Tax ReductiontoOperatingExpensesInAssociationWithSpectrumRepackMandateNetofTax	900000	USD
CY2019Q4	ghc	Reductionto Operating Expenses In Association With Spectrum Repack Mandate Netof Tax ReductiontoOperatingExpensesInAssociationWithSpectrumRepackMandateNetofTax	800000	USD
CY2019	ghc	Reductionto Operating Expenses In Association With Spectrum Repack Mandate Netof Tax ReductiontoOperatingExpensesInAssociationWithSpectrumRepackMandateNetofTax	9100000	USD
CY2019Q4	ghc	Settlement Gain Relatedto Pension Annuity Purchase After Tax SettlementGainRelatedtoPensionAnnuityPurchaseAfterTax	66900000	USD
CY2019	ghc	Settlement Gain Relatedto Pension Annuity Purchase After Tax SettlementGainRelatedtoPensionAnnuityPurchaseAfterTax	66900000	USD
CY2019Q1	ghc	Write Upsof Cost Method Investments After Tax WriteUpsofCostMethodInvestmentsAfterTax	1100000	USD
CY2019Q3	ghc	Write Upsof Cost Method Investments After Tax WriteUpsofCostMethodInvestmentsAfterTax	2800000	USD
CY2019	ghc	Write Upsof Cost Method Investments After Tax WriteUpsofCostMethodInvestmentsAfterTax	3900000	USD
CY2018Q4	us-gaap	Allowance For Doubtful Accounts Receivable AllowanceForDoubtfulAccountsReceivable	14775000	USD
CY2019Q4	us-gaap	Allowance For Doubtful Accounts Receivable AllowanceForDoubtfulAccountsReceivable	14276000	USD
CY2018Q1	us-gaap	Effective Income Tax Rate Reconciliation Share Based Compensation Excess Tax Benefit Amount EffectiveIncomeTaxRateReconciliationShareBasedCompensationExcessTaxBenefitAmount	1800000	USD
CY2019Q4	us-gaap	Preferred Stock Shares Authorized PreferredStockSharesAuthorized	977000	shares
CY2019Q1	us-gaap	Effective Income Tax Rate Reconciliation Share Based Compensation Excess Tax Benefit Amount EffectiveIncomeTaxRateReconciliationShareBasedCompensationExcessTaxBenefitAmount	-1700000	USD
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Share Based Compensation Excess Tax Benefit Amount EffectiveIncomeTaxRateReconciliationShareBasedCompensationExcessTaxBenefitAmount	-1700000	USD
CY2018Q4	us-gaap	Preferred Stock Shares Issued PreferredStockSharesIssued	0	shares
CY2019Q4	us-gaap	Preferred Stock Shares Issued PreferredStockSharesIssued	0	shares
CY2019Q4	us-gaap	Unrecognized Tax Benefits Income Tax Penalties Accrued UnrecognizedTaxBenefitsIncomeTaxPenaltiesAccrued	0	USD
CY2019	dei	Document Type DocumentType	10-K
CY2019	dei	Document Annual Report DocumentAnnualReport	true
CY2019	dei	Document Period End Date DocumentPeriodEndDate	2019-12-31
CY2018Q4	us-gaap	Line Of Credit LineOfCredit	0	USD
CY2018Q4	us-gaap	Preferred Stock Par Or Stated Value Per Share PreferredStockParOrStatedValuePerShare	1
CY2019Q4	us-gaap	Preferred Stock Par Or Stated Value Per Share PreferredStockParOrStatedValuePerShare	1
CY2018Q4	us-gaap	Preferred Stock Shares Authorized PreferredStockSharesAuthorized	977000	shares
CY2019	dei	Document Transition Report DocumentTransitionReport	false
CY2019	dei	Entity File Number EntityFileNumber	001-06714
CY2019	dei	Entity Registrant Name EntityRegistrantName	Graham Holdings Co
CY2019	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	DE
CY2019	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	53-0182885
CY2019	dei	Entity Address Address Line1 EntityAddressAddressLine1	1300 North 17th Street
CY2019	dei	Entity Address City Or Town EntityAddressCityOrTown	Arlington
CY2019	dei	Entity Address State Or Province EntityAddressStateOrProvince	VA
CY2019	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	22209
CY2019	dei	City Area Code CityAreaCode	703
CY2019	dei	Local Phone Number LocalPhoneNumber	345-6300
CY2019	dei	Security12b Title Security12bTitle	Class B Common Stock, par value$1.00 per share
CY2019	dei	Trading Symbol TradingSymbol	GHC
CY2019	dei	Security Exchange Name SecurityExchangeName	NYSE
CY2019	dei	Entity Well Known Seasoned Issuer EntityWellKnownSeasonedIssuer	Yes
CY2019	dei	Entity Voluntary Filers EntityVoluntaryFilers	No
CY2019	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
CY2019	dei	Entity Interactive Data Current EntityInteractiveDataCurrent	Yes
CY2019	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
CY2019	dei	Entity Small Business EntitySmallBusiness	false
CY2019	dei	Entity Emerging Growth Company EntityEmergingGrowthCompany	false
CY2019	dei	Entity Shell Company EntityShellCompany	false
CY2018Q2	dei	Entity Public Float EntityPublicFloat	3000000000	USD
CY2019	us-gaap	Revenues Revenues	2932099000	USD
CY2018	us-gaap	Revenues Revenues	2695966000	USD
CY2017	us-gaap	Revenues Revenues	2591846000	USD
CY2019	ghc	Operating Expense OperatingExpense	2023205000	USD
CY2018	ghc	Operating Expense OperatingExpense	1687432000	USD
CY2017	ghc	Operating Expense OperatingExpense	1454343000	USD
CY2019	ghc	Selling Generaland Administrative Expenses SellingGeneralandAdministrativeExpenses	642700000	USD
CY2018	ghc	Selling Generaland Administrative Expenses SellingGeneralandAdministrativeExpenses	650128000	USD
CY2017	ghc	Selling Generaland Administrative Expenses SellingGeneralandAdministrativeExpenses	887790000	USD
CY2019	us-gaap	Depreciation Depreciation	59253000	USD
CY2018	us-gaap	Depreciation Depreciation	56722000	USD
CY2017	us-gaap	Depreciation Depreciation	62509000	USD
CY2019	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	53243000	USD
CY2018	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	47414000	USD
CY2017	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	41187000	USD
CY2019	us-gaap	Asset Impairment Charges AssetImpairmentCharges	9152000	USD
CY2018	us-gaap	Asset Impairment Charges AssetImpairmentCharges	8109000	USD
CY2017	us-gaap	Asset Impairment Charges AssetImpairmentCharges	9614000	USD
CY2019	us-gaap	Costs And Expenses CostsAndExpenses	2787553000	USD
CY2018	us-gaap	Costs And Expenses CostsAndExpenses	2449805000	USD
CY2017	us-gaap	Costs And Expenses CostsAndExpenses	2455443000	USD
CY2019	us-gaap	Operating Income Loss OperatingIncomeLoss	144546000	USD
CY2018	us-gaap	Operating Income Loss OperatingIncomeLoss	246161000	USD
CY2017	us-gaap	Operating Income Loss OperatingIncomeLoss	136403000	USD
CY2019	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	11664000	USD
CY2018	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	14473000	USD
CY2017	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	-3249000	USD
CY2019	us-gaap	Investment Income Interest InvestmentIncomeInterest	6151000	USD
CY2018	us-gaap	Investment Income Interest InvestmentIncomeInterest	5353000	USD
CY2017	us-gaap	Investment Income Interest InvestmentIncomeInterest	6581000	USD
CY2019	us-gaap	Interest Expense InterestExpense	29779000	USD
CY2018	us-gaap	Interest Expense InterestExpense	37902000	USD
CY2017	us-gaap	Interest Expense InterestExpense	33886000	USD
CY2019	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	0	USD
CY2018	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	-11378000	USD
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CY2019	us-gaap	Net Periodic Defined Benefits Expense Reversal Of Expense Excluding Service Cost Component NetPeriodicDefinedBenefitsExpenseReversalOfExpenseExcludingServiceCostComponent	-162798000	USD
CY2018	us-gaap	Net Periodic Defined Benefits Expense Reversal Of Expense Excluding Service Cost Component NetPeriodicDefinedBenefitsExpenseReversalOfExpenseExcludingServiceCostComponent	-120541000	USD
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CY2019	us-gaap	Equity Securities Fv Ni Gain Loss EquitySecuritiesFvNiGainLoss	98668000	USD
CY2018	us-gaap	Equity Securities Fv Ni Gain Loss EquitySecuritiesFvNiGainLoss	-15843000	USD
CY2019	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	32431000	USD
CY2017	us-gaap	Equity Securities Fv Ni Gain Loss EquitySecuritiesFvNiGainLoss	0	USD
CY2018	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	2103000	USD
CY2017	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	4241000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	426479000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	323508000	USD
CY2017	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	182789000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	98600000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	52100000	USD
CY2017	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-119700000	USD
CY2019	us-gaap	Profit Loss ProfitLoss	327879000	USD
CY2018	us-gaap	Profit Loss ProfitLoss	271408000	USD
CY2017	us-gaap	Profit Loss ProfitLoss	302489000	USD
CY2019	ghc	Income Loss Attributableto Redeemable Noncontrolling Interestand Nonredeemable Noncontrolling Interest IncomeLossAttributabletoRedeemableNoncontrollingInterestandNonredeemableNoncontrollingInterest	24000	USD
CY2018	ghc	Income Loss Attributableto Redeemable Noncontrolling Interestand Nonredeemable Noncontrolling Interest IncomeLossAttributabletoRedeemableNoncontrollingInterestandNonredeemableNoncontrollingInterest	202000	USD
CY2017	ghc	Income Loss Attributableto Redeemable Noncontrolling Interestand Nonredeemable Noncontrolling Interest IncomeLossAttributabletoRedeemableNoncontrollingInterestandNonredeemableNoncontrollingInterest	445000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	327855000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	271206000	USD
CY2017	us-gaap	Net Income Loss NetIncomeLoss	302044000	USD
CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	61.70
CY2018	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	50.55
CY2017	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	54.24
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	5285000	shares
CY2018	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	5333000	shares
CY2017	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	5516000	shares
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	61.21
CY2018	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	50.20
CY2017	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	53.89
CY2019	ghc	Weighted Average Number Of Potentially Dilutive Shares Outstanding WeightedAverageNumberOfPotentiallyDilutiveSharesOutstanding	5327000	shares
CY2018	ghc	Weighted Average Number Of Potentially Dilutive Shares Outstanding WeightedAverageNumberOfPotentiallyDilutiveSharesOutstanding	5370000	shares
CY2017	ghc	Weighted Average Number Of Potentially Dilutive Shares Outstanding WeightedAverageNumberOfPotentiallyDilutiveSharesOutstanding	5552000	shares
CY2019	us-gaap	Profit Loss ProfitLoss	327879000	USD
CY2018	us-gaap	Profit Loss ProfitLoss	271408000	USD
CY2017	us-gaap	Profit Loss ProfitLoss	302489000	USD
CY2019	us-gaap	Other Comprehensive Income Foreign Currency Transaction And Translation Gain Loss Before Reclassification And Tax OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationGainLossBeforeReclassificationAndTax	5371000	USD
CY2018	us-gaap	Other Comprehensive Income Foreign Currency Transaction And Translation Gain Loss Before Reclassification And Tax OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationGainLossBeforeReclassificationAndTax	-35584000	USD
CY2017	us-gaap	Other Comprehensive Income Foreign Currency Transaction And Translation Gain Loss Before Reclassification And Tax OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationGainLossBeforeReclassificationAndTax	33175000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Reclassification Adjustment From Aoci Realized Upon Sale Or Liquidation Before Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationReclassificationAdjustmentFromAOCIRealizedUponSaleOrLiquidationBeforeTax	-2011000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Reclassification Adjustment From Aoci Realized Upon Sale Or Liquidation Before Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationReclassificationAdjustmentFromAOCIRealizedUponSaleOrLiquidationBeforeTax	0	USD
CY2017	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Reclassification Adjustment From Aoci Realized Upon Sale Or Liquidation Before Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationReclassificationAdjustmentFromAOCIRealizedUponSaleOrLiquidationBeforeTax	-137000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Before Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentBeforeTax	7382000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Before Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentBeforeTax	-35584000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Before Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentBeforeTax	33312000	USD
CY2019	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	0	USD
CY2018	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	0	USD
CY2017	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	112086000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Net Unamortized Gain Loss Arising During Period Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansNetUnamortizedGainLossArisingDuringPeriodBeforeTax	231104000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Net Unamortized Gain Loss Arising During Period Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansNetUnamortizedGainLossArisingDuringPeriodBeforeTax	-101013000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Net Unamortized Gain Loss Arising During Period Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansNetUnamortizedGainLossArisingDuringPeriodBeforeTax	179674000	USD
CY2019	us-gaap	Other Comprehensive Income Defined Benefit Plan Net Prior Service Cost Credit Arising During Period Before Tax OtherComprehensiveIncomeDefinedBenefitPlanNetPriorServiceCostCreditArisingDuringPeriodBeforeTax	5725000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax	6527000	USD
CY2018	us-gaap	Other Comprehensive Income Defined Benefit Plan Net Prior Service Cost Credit Arising During Period Before Tax OtherComprehensiveIncomeDefinedBenefitPlanNetPriorServiceCostCreditArisingDuringPeriodBeforeTax	-4262000	USD
CY2017	us-gaap	Other Comprehensive Income Defined Benefit Plan Net Prior Service Cost Credit Arising During Period Before Tax OtherComprehensiveIncomeDefinedBenefitPlanNetPriorServiceCostCreditArisingDuringPeriodBeforeTax	75000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax	2046000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax	11349000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Before Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditBeforeTax	-4142000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Before Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditBeforeTax	-947000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Before Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditBeforeTax	477000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Finalization Of Pension And Non Pension Postretirement Plan Valuation Before Tax OtherComprehensiveIncomeLossFinalizationOfPensionAndNonPensionPostretirementPlanValuationBeforeTax	-91676000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Finalization Of Pension And Non Pension Postretirement Plan Valuation Before Tax OtherComprehensiveIncomeLossFinalizationOfPensionAndNonPensionPostretirementPlanValuationBeforeTax	-30267000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Finalization Of Pension And Non Pension Postretirement Plan Valuation Before Tax OtherComprehensiveIncomeLossFinalizationOfPensionAndNonPensionPostretirementPlanValuationBeforeTax	0	USD
CY2019	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeTax	-127515000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeTax	139314000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeTax	-173549000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification Before Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationBeforeTax	-1344000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Derivatives Qualifying As Hedges Before Tax OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesBeforeTax	551000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Derivatives Qualifying As Hedges Before Tax OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesBeforeTax	112000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	133553000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	-174347000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	319059000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	34087000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	-37510000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	90923000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	99466000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-136837000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	228136000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	427345000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	134571000	USD
CY2017	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	530625000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	24000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	202000	USD
CY2017	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	445000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	427321000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	134369000	USD
CY2017	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	530180000	USD
CY2019Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	200165000	USD
CY2018Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	253256000	USD
CY2019Q4	us-gaap	Restricted Cash And Cash Equivalents RestrictedCashAndCashEquivalents	13879000	USD
CY2018Q4	us-gaap	Restricted Cash And Cash Equivalents RestrictedCashAndCashEquivalents	10859000	USD
CY2019Q4	ghc	Investments In Marketable Equity Securities And Other Investments InvestmentsInMarketableEquitySecuritiesAndOtherInvestments	599967000	USD
CY2018Q4	ghc	Investments In Marketable Equity Securities And Other Investments InvestmentsInMarketableEquitySecuritiesAndOtherInvestments	514581000	USD
CY2019Q4	us-gaap	Accounts And Other Receivables Net Current AccountsAndOtherReceivablesNetCurrent	624216000	USD
CY2018Q4	us-gaap	Accounts And Other Receivables Net Current AccountsAndOtherReceivablesNetCurrent	582280000	USD
CY2019Q4	us-gaap	Income Taxes Receivable IncomeTaxesReceivable	10735000	USD
CY2018Q4	us-gaap	Income Taxes Receivable IncomeTaxesReceivable	19166000	USD
CY2019Q4	us-gaap	Inventory Net Of Allowances Customer Advances And Progress Billings InventoryNetOfAllowancesCustomerAdvancesAndProgressBillings	108928000	USD
CY2018Q4	us-gaap	Inventory Net Of Allowances Customer Advances And Progress Billings InventoryNetOfAllowancesCustomerAdvancesAndProgressBillings	69477000	USD
CY2019Q4	us-gaap	Other Assets Current OtherAssetsCurrent	105595000	USD
CY2018Q4	us-gaap	Other Assets Current OtherAssetsCurrent	82723000	USD
CY2019Q4	us-gaap	Assets Current AssetsCurrent	1663485000	USD
CY2018Q4	us-gaap	Assets Current AssetsCurrent	1532342000	USD
CY2019Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	384670000	USD
CY2018Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	293085000	USD
CY2019Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	526417000	USD
CY2018Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	0	USD
CY2019Q4	us-gaap	Investments In Affiliates Subsidiaries Associates And Joint Ventures InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures	162249000	USD
CY2018Q4	us-gaap	Investments In Affiliates Subsidiaries Associates And Joint Ventures InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures	143813000	USD
CY2019Q4	us-gaap	Goodwill Goodwill	1388279000	USD
CY2018Q4	us-gaap	Goodwill Goodwill	1297712000	USD
CY2019Q4	us-gaap	Indefinite Lived Intangible Assets Excluding Goodwill IndefiniteLivedIntangibleAssetsExcludingGoodwill	140197000	USD
CY2018Q4	us-gaap	Indefinite Lived Intangible Assets Excluding Goodwill IndefiniteLivedIntangibleAssetsExcludingGoodwill	99052000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	233481000	USD
CY2018Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	263261000	USD
CY2019Q4	us-gaap	Defined Benefit Plan Assets For Plan Benefits Noncurrent DefinedBenefitPlanAssetsForPlanBenefitsNoncurrent	1292350000	USD
CY2018Q4	us-gaap	Defined Benefit Plan Assets For Plan Benefits Noncurrent DefinedBenefitPlanAssetsForPlanBenefitsNoncurrent	1003558000	USD
CY2019Q4	us-gaap	Deferred Income Tax Assets Net DeferredIncomeTaxAssetsNet	11629000	USD
CY2018Q4	us-gaap	Deferred Income Tax Assets Net DeferredIncomeTaxAssetsNet	13388000	USD
CY2019Q4	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	128479000	USD
CY2018Q4	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	117830000	USD
CY2019Q4	us-gaap	Assets Assets	5931236000	USD
CY2018Q4	us-gaap	Assets Assets	4764041000	USD
CY2019Q4	us-gaap	Accounts Payable And Accrued Liabilities Current AccountsPayableAndAccruedLiabilitiesCurrent	507701000	USD
CY2018Q4	us-gaap	Accounts Payable And Accrued Liabilities Current AccountsPayableAndAccruedLiabilitiesCurrent	486578000	USD
CY2019Q4	us-gaap	Deferred Revenue Current DeferredRevenueCurrent	355156000	USD
CY2018Q4	us-gaap	Deferred Revenue Current DeferredRevenueCurrent	308728000	USD
CY2019Q4	us-gaap	Accrued Income Taxes Current AccruedIncomeTaxesCurrent	4121000	USD
CY2018Q4	us-gaap	Accrued Income Taxes Current AccruedIncomeTaxesCurrent	10496000	USD
CY2019Q4	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	92714000	USD
CY2018Q4	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	0	USD
CY2019Q4	us-gaap	Debt Current DebtCurrent	82179000	USD
CY2018Q4	us-gaap	Liabilities Current LiabilitiesCurrent	812162000	USD
CY2018Q4	us-gaap	Debt Current DebtCurrent	6360000	USD
CY2019Q4	us-gaap	Liabilities Current LiabilitiesCurrent	1041871000	USD
CY2019Q4	us-gaap	Deferred Compensation Liability Classified Noncurrent DeferredCompensationLiabilityClassifiedNoncurrent	193836000	USD
CY2018Q4	us-gaap	Deferred Compensation Liability Classified Noncurrent DeferredCompensationLiabilityClassifiedNoncurrent	179652000	USD
CY2019Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	27223000	USD
CY2018Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	57901000	USD
CY2019Q4	us-gaap	Shares Subject To Mandatory Redemption Settlement Terms Amount Noncurrent SharesSubjectToMandatoryRedemptionSettlementTermsAmountNoncurrent	829000	USD
CY2019Q4	us-gaap	Deferred Income Tax Liabilities Net DeferredIncomeTaxLiabilitiesNet	427372000	USD
CY2018Q4	us-gaap	Deferred Income Tax Liabilities Net DeferredIncomeTaxLiabilitiesNet	322421000	USD
CY2018Q4	us-gaap	Shares Subject To Mandatory Redemption Settlement Terms Amount Noncurrent SharesSubjectToMandatoryRedemptionSettlementTermsAmountNoncurrent	0	USD
CY2019Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	477004000	USD
CY2018Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	0	USD
CY2019Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	430650000	USD
CY2018Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	470777000	USD
CY2019Q4	us-gaap	Liabilities Liabilities	2598785000	USD
CY2018Q4	us-gaap	Liabilities Liabilities	1842913000	USD
CY2019Q4	us-gaap	Commitments And Contingencies CommitmentsAndContingencies		USD
CY2018Q4	us-gaap	Commitments And Contingencies CommitmentsAndContingencies		USD
CY2019Q4	us-gaap	Redeemable Noncontrolling Interest Equity Carrying Amount RedeemableNoncontrollingInterestEquityCarryingAmount	5655000	USD
CY2018Q4	us-gaap	Redeemable Noncontrolling Interest Equity Carrying Amount RedeemableNoncontrollingInterestEquityCarryingAmount	4346000	USD
CY2019Q4	us-gaap	Preferred Stock Value PreferredStockValue	0	USD
CY2018Q4	us-gaap	Preferred Stock Value PreferredStockValue	0	USD
CY2019Q4	us-gaap	Additional Paid In Capital AdditionalPaidInCapital	381669000	USD
CY2018Q4	us-gaap	Additional Paid In Capital AdditionalPaidInCapital	378837000	USD
CY2019Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	6534427000	USD
CY2018Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	6236125000	USD
CY2019Q4	us-gaap	Accumulated Other Comprehensive Income Loss Foreign Currency Translation Adjustment Net Of Tax AccumulatedOtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentNetOfTax	-21888000	USD
CY2018Q4	us-gaap	Accumulated Other Comprehensive Income Loss Foreign Currency Translation Adjustment Net Of Tax AccumulatedOtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentNetOfTax	-29270000	USD
CY2019Q4	us-gaap	Accumulated Other Comprehensive Income Loss Defined Benefit Pension And Other Postretirement Plans Net Of Tax AccumulatedOtherComprehensiveIncomeLossDefinedBenefitPensionAndOtherPostretirementPlansNetOfTax	-325921000	USD
CY2018Q4	us-gaap	Accumulated Other Comprehensive Income Loss Defined Benefit Pension And Other Postretirement Plans Net Of Tax AccumulatedOtherComprehensiveIncomeLossDefinedBenefitPensionAndOtherPostretirementPlansNetOfTax	-232836000	USD
CY2019Q4	us-gaap	Accumulated Other Comprehensive Income Loss Cumulative Changes In Net Gain Loss From Cash Flow Hedges Effect Net Of Tax AccumulatedOtherComprehensiveIncomeLossCumulativeChangesInNetGainLossFromCashFlowHedgesEffectNetOfTax	-738000	USD
CY2018Q4	us-gaap	Accumulated Other Comprehensive Income Loss Cumulative Changes In Net Gain Loss From Cash Flow Hedges Effect Net Of Tax AccumulatedOtherComprehensiveIncomeLossCumulativeChangesInNetGainLossFromCashFlowHedgesEffectNetOfTax	263000	USD
CY2019Q4	us-gaap	Treasury Stock Value TreasuryStockValue	3920152000	USD
CY2018Q4	us-gaap	Treasury Stock Value TreasuryStockValue	3922009000	USD
CY2019Q4	us-gaap	Stockholders Equity StockholdersEquity	3319239000	USD
CY2018Q4	us-gaap	Stockholders Equity StockholdersEquity	2916782000	USD
CY2019Q4	us-gaap	Minority Interest MinorityInterest	7557000	USD
CY2018Q4	us-gaap	Minority Interest MinorityInterest	0	USD
CY2019Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	3326796000	USD
CY2018Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	2916782000	USD
CY2019Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	5931236000	USD
CY2018Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	4764041000	USD
CY2019	us-gaap	Profit Loss ProfitLoss	327879000	USD
CY2018	us-gaap	Profit Loss ProfitLoss	271408000	USD
CY2017	us-gaap	Profit Loss ProfitLoss	302489000	USD
CY2019	ghc	Depreciation Depletion Amortization And Impairment DepreciationDepletionAmortizationAndImpairment	121648000	USD
CY2018	ghc	Depreciation Depletion Amortization And Impairment DepreciationDepletionAmortizationAndImpairment	112245000	USD
CY2017	ghc	Depreciation Depletion Amortization And Impairment DepreciationDepletionAmortizationAndImpairment	113310000	USD
CY2019	ghc	Operating Lease Right Of Use Asset Amortization OperatingLeaseRightOfUseAssetAmortization	84185000	USD
CY2018	ghc	Operating Lease Right Of Use Asset Amortization OperatingLeaseRightOfUseAssetAmortization	0	USD
CY2017	ghc	Operating Lease Right Of Use Asset Amortization OperatingLeaseRightOfUseAssetAmortization	0	USD
CY2019	ghc	Net Periodic Benefit For Defined Benefit Pension Plans Excluding Curtailment NetPeriodicBenefitForDefinedBenefitPensionPlansExcludingCurtailment	-137909000	USD
CY2018	ghc	Net Periodic Benefit For Defined Benefit Pension Plans Excluding Curtailment NetPeriodicBenefitForDefinedBenefitPensionPlansExcludingCurtailment	-100948000	USD
CY2017	ghc	Net Periodic Benefit For Defined Benefit Pension Plans Excluding Curtailment NetPeriodicBenefitForDefinedBenefitPensionPlansExcludingCurtailment	-57214000	USD
CY2019	us-gaap	Unrealized Gain Loss On Investments UnrealizedGainLossOnInvestments	103748000	USD
CY2018	us-gaap	Unrealized Gain Loss On Investments UnrealizedGainLossOnInvestments	-4180000	USD
CY2017	us-gaap	Unrealized Gain Loss On Investments UnrealizedGainLossOnInvestments	0	USD
CY2019	ghc	Provision For Doubtful Trade And Other Receivables ProvisionForDoubtfulTradeAndOtherReceivables	22726000	USD
CY2018	ghc	Provision For Doubtful Trade And Other Receivables ProvisionForDoubtfulTradeAndOtherReceivables	10209000	USD
CY2017	ghc	Provision For Doubtful Trade And Other Receivables ProvisionForDoubtfulTradeAndOtherReceivables	33830000	USD
CY2019	us-gaap	Share Based Compensation ShareBasedCompensation	6278000	USD
CY2018	us-gaap	Share Based Compensation ShareBasedCompensation	6412000	USD
CY2017	us-gaap	Share Based Compensation ShareBasedCompensation	10169000	USD
CY2019	us-gaap	Gains Losses On Extinguishment Of Debt Before Write Off Of Deferred Debt Issuance Cost GainsLossesOnExtinguishmentOfDebtBeforeWriteOffOfDeferredDebtIssuanceCost	0	USD
CY2018	us-gaap	Gains Losses On Extinguishment Of Debt Before Write Off Of Deferred Debt Issuance Cost GainsLossesOnExtinguishmentOfDebtBeforeWriteOffOfDeferredDebtIssuanceCost	-10563000	USD
CY2017	us-gaap	Gains Losses On Extinguishment Of Debt Before Write Off Of Deferred Debt Issuance Cost GainsLossesOnExtinguishmentOfDebtBeforeWriteOffOfDeferredDebtIssuanceCost	0	USD
CY2019	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	-1070000	USD
CY2018	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	-3844000	USD
CY2017	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	3310000	USD
CY2019	ghc	Net Gain Loss On Sales And Dispositionof Businesses NetGainLossOnSalesAndDispositionofBusinesses	-1936000	USD
CY2018	ghc	Net Gain Loss On Sales And Dispositionof Businesses NetGainLossOnSalesAndDispositionofBusinesses	8157000	USD
CY2017	ghc	Net Gain Loss On Sales And Dispositionof Businesses NetGainLossOnSalesAndDispositionofBusinesses	-569000	USD
CY2019	ghc	Marketable Securities And Cost Method Investments Realized Gain Loss MarketableSecuritiesAndCostMethodInvestmentsRealizedGainLoss	29262000	USD
CY2018	ghc	Marketable Securities And Cost Method Investments Realized Gain Loss MarketableSecuritiesAndCostMethodInvestmentsRealizedGainLoss	148000	USD
CY2017	ghc	Marketable Securities And Cost Method Investments Realized Gain Loss MarketableSecuritiesAndCostMethodInvestmentsRealizedGainLoss	-200000	USD
CY2019	us-gaap	Income Loss From Equity Method Investments Net Of Dividends Or Distributions IncomeLossFromEquityMethodInvestmentsNetOfDividendsOrDistributions	2678000	USD
CY2018	us-gaap	Income Loss From Equity Method Investments Net Of Dividends Or Distributions IncomeLossFromEquityMethodInvestmentsNetOfDividendsOrDistributions	10606000	USD
CY2017	us-gaap	Income Loss From Equity Method Investments Net Of Dividends Or Distributions IncomeLossFromEquityMethodInvestmentsNetOfDividendsOrDistributions	-3646000	USD
CY2019	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	69751000	USD
CY2018	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-7123000	USD
CY2017	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-146452000	USD
CY2019	ghc	Gain Loss On Sale Or Writedown Of Property Plant Equipment GainLossOnSaleOrWritedownOfPropertyPlantEquipment	1020000	USD
CY2018	ghc	Gain Loss On Sale Or Writedown Of Property Plant Equipment GainLossOnSaleOrWritedownOfPropertyPlantEquipment	1642000	USD
CY2017	ghc	Gain Loss On Sale Or Writedown Of Property Plant Equipment GainLossOnSaleOrWritedownOfPropertyPlantEquipment	-413000	USD
CY2019	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	53602000	USD
CY2018	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	-49638000	USD
CY2017	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	22744000	USD
CY2019	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	5317000	USD
CY2018	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	7351000	USD
CY2017	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	541000	USD
CY2019	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	-47069000	USD
CY2018	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	-44892000	USD
CY2017	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	19380000	USD
CY2019	us-gaap	Increase Decrease In Deferred Revenue IncreaseDecreaseInDeferredRevenue	30487000	USD
CY2018	us-gaap	Increase Decrease In Deferred Revenue IncreaseDecreaseInDeferredRevenue	14801000	USD
CY2017	us-gaap	Increase Decrease In Deferred Revenue IncreaseDecreaseInDeferredRevenue	13903000	USD
CY2019	us-gaap	Increase Decrease In Income Taxes IncreaseDecreaseInIncomeTaxes	1828000	USD
CY2018	us-gaap	Increase Decrease In Income Taxes IncreaseDecreaseInIncomeTaxes	9405000	USD
CY2017	us-gaap	Increase Decrease In Income Taxes IncreaseDecreaseInIncomeTaxes	24739000	USD
CY2019	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	122252000	USD
CY2018	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	26973000	USD
CY2017	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	25469000	USD
CY2019	us-gaap	Other Operating Activities Cash Flow Statement OtherOperatingActivitiesCashFlowStatement	233000	USD
CY2018	us-gaap	Other Operating Activities Cash Flow Statement OtherOperatingActivitiesCashFlowStatement	2154000	USD
CY2017	us-gaap	Other Operating Activities Cash Flow Statement OtherOperatingActivitiesCashFlowStatement	1137000	USD
CY2019	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	165164000	USD
CY2018	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	287019000	USD
CY2017	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	268055000	USD
CY2019	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	179421000	USD
CY2018	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	111546000	USD
CY2017	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	299938000	USD
CY2019	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	93504000	USD
CY2018	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	98192000	USD
CY2017	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	60358000	USD
CY2019	us-gaap	Proceeds From Sale And Maturity Of Marketable Securities ProceedsFromSaleAndMaturityOfMarketableSecurities	19303000	USD
CY2018	us-gaap	Proceeds From Sale And Maturity Of Marketable Securities ProceedsFromSaleAndMaturityOfMarketableSecurities	66741000	USD
CY2017	us-gaap	Proceeds From Sale And Maturity Of Marketable Securities ProceedsFromSaleAndMaturityOfMarketableSecurities	0	USD
CY2019	us-gaap	Payments To Acquire Marketable Securities PaymentsToAcquireMarketableSecurities	7499000	USD
CY2018	us-gaap	Payments To Acquire Marketable Securities PaymentsToAcquireMarketableSecurities	42659000	USD
CY2017	us-gaap	Payments To Acquire Marketable Securities PaymentsToAcquireMarketableSecurities	0	USD
CY2019	ghc	Advance Related To Kaplan University Transaction And Loans To Affiliate And Relat Party AdvanceRelatedToKaplanUniversityTransactionAndLoansToAffiliateAndRelatParty	3500000	USD
CY2018	ghc	Advance Related To Kaplan University Transaction And Loans To Affiliate And Relat Party AdvanceRelatedToKaplanUniversityTransactionAndLoansToAffiliateAndRelatParty	28061000	USD
CY2017	ghc	Advance Related To Kaplan University Transaction And Loans To Affiliate And Relat Party AdvanceRelatedToKaplanUniversityTransactionAndLoansToAffiliateAndRelatParty	6771000	USD
CY2019	ghc	Payments To Acquire Equity Method Cost Method Investments And Other Investments PaymentsToAcquireEquityMethodCostMethodInvestmentsAndOtherInvestments	27529000	USD
CY2018	ghc	Payments To Acquire Equity Method Cost Method Investments And Other Investments PaymentsToAcquireEquityMethodCostMethodInvestmentsAndOtherInvestments	11702000	USD
CY2017	ghc	Payments To Acquire Equity Method Cost Method Investments And Other Investments PaymentsToAcquireEquityMethodCostMethodInvestmentsAndOtherInvestments	82944000	USD
CY2019	ghc	Net Proceeds From Sale Of Businesses Property Plant And Equipment And Other Assets NetProceedsFromSaleOfBusinessesPropertyPlantAndEquipmentAndOtherAssets	54495000	USD
CY2018	ghc	Net Proceeds From Sale Of Businesses Property Plant And Equipment And Other Assets NetProceedsFromSaleOfBusinessesPropertyPlantAndEquipmentAndOtherAssets	-10344000	USD
CY2017	ghc	Net Proceeds From Sale Of Businesses Property Plant And Equipment And Other Assets NetProceedsFromSaleOfBusinessesPropertyPlantAndEquipmentAndOtherAssets	3265000	USD
CY2019	us-gaap	Proceeds From Equity Method Investment Dividends Or Distributions Return Of Capital ProceedsFromEquityMethodInvestmentDividendsOrDistributionsReturnOfCapital	920000	USD
CY2018	us-gaap	Proceeds From Equity Method Investment Dividends Or Distributions Return Of Capital ProceedsFromEquityMethodInvestmentDividendsOrDistributionsReturnOfCapital	4799000	USD
CY2017	us-gaap	Proceeds From Equity Method Investment Dividends Or Distributions Return Of Capital ProceedsFromEquityMethodInvestmentDividendsOrDistributionsReturnOfCapital	4727000	USD
CY2019	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-236735000	USD
CY2018	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-230964000	USD
CY2017	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-442019000	USD
CY2019	ghc	Repayments Of Long Term Debt And Debt Extinguishment Costs RepaymentsOfLongTermDebtAndDebtExtinguishmentCosts	8702000	USD
CY2018	ghc	Repayments Of Long Term Debt And Debt Extinguishment Costs RepaymentsOfLongTermDebtAndDebtExtinguishmentCosts	417159000	USD
CY2017	ghc	Repayments Of Long Term Debt And Debt Extinguishment Costs RepaymentsOfLongTermDebtAndDebtExtinguishmentCosts	7715000	USD
CY2019	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	41250000	USD
CY2018	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	400000000	USD
CY2017	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	0	USD
CY2019	ghc	Proceeds From Payments Of Vehicle Floor Plan Payable Net ProceedsFromPaymentsOfVehicleFloorPlanPayableNet	14384000	USD
CY2018	ghc	Proceeds From Payments Of Vehicle Floor Plan Payable Net ProceedsFromPaymentsOfVehicleFloorPlanPayableNet	0	USD
CY2017	ghc	Proceeds From Payments Of Vehicle Floor Plan Payable Net ProceedsFromPaymentsOfVehicleFloorPlanPayableNet	0	USD
CY2019	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	2103000	USD
CY2018	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	118030000	USD
CY2017	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	50770000	USD
CY2019	us-gaap	Payments Of Ordinary Dividends PaymentsOfOrdinaryDividends	29553000	USD
CY2018	us-gaap	Payments Of Ordinary Dividends PaymentsOfOrdinaryDividends	28617000	USD
CY2017	us-gaap	Payments Of Ordinary Dividends PaymentsOfOrdinaryDividends	28329000	USD
CY2019	ghc	Purchaseof Noncontrolling Interestand Deferred Paymentof Acquisition PurchaseofNoncontrollingInterestandDeferredPaymentofAcquisition	2805000	USD
CY2018	ghc	Purchaseof Noncontrolling Interestand Deferred Paymentof Acquisition PurchaseofNoncontrollingInterestandDeferredPaymentofAcquisition	16500000	USD
CY2017	ghc	Purchaseof Noncontrolling Interestand Deferred Paymentof Acquisition PurchaseofNoncontrollingInterestandDeferredPaymentofAcquisition	5187000	USD
CY2019	us-gaap	Payments Of Financing Costs PaymentsOfFinancingCosts	33000	USD
CY2018	us-gaap	Payments Of Financing Costs PaymentsOfFinancingCosts	6501000	USD
CY2017	us-gaap	Payments Of Financing Costs PaymentsOfFinancingCosts	0	USD
CY2019	us-gaap	Proceeds From Repayments Of Bank Overdrafts ProceedsFromRepaymentsOfBankOverdrafts	-185000	USD
CY2018	us-gaap	Proceeds From Repayments Of Bank Overdrafts ProceedsFromRepaymentsOfBankOverdrafts	-5717000	USD
CY2017	us-gaap	Proceeds From Repayments Of Bank Overdrafts ProceedsFromRepaymentsOfBankOverdrafts	-9505000	USD
CY2019	us-gaap	Proceeds From Minority Shareholders ProceedsFromMinorityShareholders	6000000	USD
CY2018	us-gaap	Proceeds From Minority Shareholders ProceedsFromMinorityShareholders	0	USD
CY2017	us-gaap	Proceeds From Minority Shareholders ProceedsFromMinorityShareholders	0	USD
CY2019	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	481000	USD
CY2018	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	165000	USD
CY2017	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	1400000	USD
CY2019	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	18734000	USD
CY2018	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-192359000	USD
CY2017	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-100106000	USD
CY2019	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	2766000	USD
CY2018	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	-7147000	USD
CY2017	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	10820000	USD
CY2019	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-50071000	USD
CY2018	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-143451000	USD
CY2017	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-263250000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	264115000	USD
CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	407566000	USD
CY2016Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	670816000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	214044000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	264115000	USD
CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	407566000	USD
CY2019	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	28000000	USD
CY2018	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	54000000	USD
CY2017	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	4000000	USD
CY2019	us-gaap	Interest Paid Net InterestPaidNet	30000000	USD
CY2018	us-gaap	Interest Paid Net InterestPaidNet	42000000	USD
CY2017	us-gaap	Interest Paid Net InterestPaidNet	33000000	USD
CY2016Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	2452941000	USD
CY2016Q4	us-gaap	Redeemable Noncontrolling Interest Equity Carrying Amount RedeemableNoncontrollingInterestEquityCarryingAmount	50000	USD
CY2017	us-gaap	Profit Loss ProfitLoss	302489000	USD
CY2017	ghc	Equity Effectof Acquisitionof Redeemable Noncontrolling Interest EquityEffectofAcquisitionofRedeemableNoncontrollingInterest	0	USD
CY2017	ghc	Acquisitionof Redeemable Noncontrolling Interest AcquisitionofRedeemableNoncontrollingInterest	3666000	USD
CY2017	us-gaap	Net Income Loss Attributable To Redeemable Noncontrolling Interest NetIncomeLossAttributableToRedeemableNoncontrollingInterest	445000	USD
CY2017	us-gaap	Temporary Equity Net Income TemporaryEquityNetIncome	445000	USD
CY2017	us-gaap	Minority Interest Change In Redemption Value MinorityInterestChangeInRedemptionValue	-446000	USD
CY2017	ghc	Temporary Equity Changein Redemption Value TemporaryEquityChangeinRedemptionValue	446000	USD
CY2017	us-gaap	Dividends Common Stock DividendsCommonStock	28329000	USD
CY2017	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	50770000	USD
CY2017	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	385000	USD
CY2017	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	11184000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	228136000	USD
CY2017	ghc	Tax Cutsand Jobs Act2017 Reclassification From Accumulated Other Comprehensive Income To Retained Earnings TaxCutsandJobsAct2017ReclassificationFromAccumulatedOtherComprehensiveIncomeToRetainedEarnings	0	USD
CY2017Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	2915145000	USD
CY2017Q4	us-gaap	Redeemable Noncontrolling Interest Equity Carrying Amount RedeemableNoncontrollingInterestEquityCarryingAmount	4607000	USD
CY2018	us-gaap	Profit Loss ProfitLoss	271408000	USD
CY2018	us-gaap	Net Income Loss Attributable To Redeemable Noncontrolling Interest NetIncomeLossAttributableToRedeemableNoncontrollingInterest	202000	USD
CY2018	us-gaap	Temporary Equity Net Income TemporaryEquityNetIncome	202000	USD
CY2018	us-gaap	Minority Interest Change In Redemption Value MinorityInterestChangeInRedemptionValue	413000	USD
CY2018	ghc	Temporary Equity Changein Redemption Value TemporaryEquityChangeinRedemptionValue	-413000	USD
CY2018	us-gaap	Dividends Common Stock DividendsCommonStock	28617000	USD
CY2018	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	118030000	USD
CY2018	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	-1485000	USD
CY2018	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	8064000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-136837000	USD
CY2018Q1	us-gaap	Cumulative Effect Of New Accounting Principle In Period Of Adoption CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption	6923000	USD
CY2018	us-gaap	Stockholders Equity Other StockholdersEquityOther	0	USD
CY2018	us-gaap	Temporary Equity Other Changes TemporaryEquityOtherChanges	-50000	USD
CY2018Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	2916782000	USD
CY2018Q4	us-gaap	Redeemable Noncontrolling Interest Equity Carrying Amount RedeemableNoncontrollingInterestEquityCarryingAmount	4346000	USD
CY2019	us-gaap	Profit Loss ProfitLoss	327879000	USD
CY2019	us-gaap	Noncontrolling Interest Increase From Subsidiary Equity Issuance NoncontrollingInterestIncreaseFromSubsidiaryEquityIssuance	6556000	USD
CY2019	ghc	Equity Effectof Acquisitionof Redeemable Noncontrolling Interest EquityEffectofAcquisitionofRedeemableNoncontrollingInterest	0	USD
CY2019	ghc	Acquisitionof Redeemable Noncontrolling Interest AcquisitionofRedeemableNoncontrollingInterest	1715000	USD
CY2019	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	0	USD
CY2019	us-gaap	Noncontrolling Interest Increase From Business Combination NoncontrollingInterestIncreaseFromBusinessCombination	1153000	USD
CY2019	us-gaap	Net Income Loss Attributable To Redeemable Noncontrolling Interest NetIncomeLossAttributableToRedeemableNoncontrollingInterest	176000	USD
CY2019	us-gaap	Temporary Equity Net Income TemporaryEquityNetIncome	176000	USD
CY2019	us-gaap	Minority Interest Change In Redemption Value MinorityInterestChangeInRedemptionValue	32000	USD
CY2019	ghc	Temporary Equity Changein Redemption Value TemporaryEquityChangeinRedemptionValue	-32000	USD
CY2019	us-gaap	Dividends Common Stock DividendsCommonStock	29553000	USD
CY2019	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	2103000	USD
CY2019	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	239000	USD
CY2019	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	6521000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	99466000	USD
CY2019	ghc	Equityeffectofredemptionofredeemablenoncontrollinginterest Equityeffectofredemptionofredeemablenoncontrollinginterest	0	USD
CY2019	us-gaap	Minority Interest Decrease From Redemptions MinorityInterestDecreaseFromRedemptions	550000	USD
CY2019Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	3326796000	USD
CY2019Q4	us-gaap	Redeemable Noncontrolling Interest Equity Carrying Amount RedeemableNoncontrollingInterestEquityCarryingAmount	5655000	USD
CY2019	us-gaap	Nature Of Operations NatureOfOperations	<div style="line-height:110%;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;font-weight:bold;">ORGANIZATION AND NATURE OF OPERATIONS</span></div><div style="line-height:110%;padding-bottom:12px;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;">Graham Holdings Company (the Company), is a diversified education and media company. The Company’s Kaplan subsidiary provides a wide variety of educational services, both domestically and outside the United States (U.S.). The Company’s media operations comprise the ownership and operation of </span><span style="font-family:Arial;font-size:10pt;"><span>seven</span></span><span style="font-family:Arial;font-size:10pt;"> television broadcasting stations.</span></div><div style="line-height:110%;padding-bottom:12px;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;font-weight:bold;">Education</span><span style="font-family:Arial;font-size:10pt;">—Kaplan, Inc. provides an extensive range of educational services for students and professionals. Kaplan’s various businesses comprise </span><span style="font-family:Arial;font-size:10pt;"><span>four</span></span><span style="font-family:Arial;font-size:10pt;"> categories: Kaplan International, Higher Education (KHE), Test Preparation (KTP) and Professional (U.S.).</span></div><div style="line-height:110%;padding-bottom:12px;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;font-weight:bold;">Media</span><span style="font-family:Arial;font-size:10pt;">—The Company’s diversified media operations comprise television broadcasting, several websites and print publications, podcast technology and a marketing solutions provider.</span></div><div style="line-height:110%;padding-bottom:12px;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;font-style:italic;">Television broadcasting. </span><span style="font-family:Arial;font-size:10pt;">As of </span><span style="font-family:Arial;font-size:10pt;">December 31, 2019</span><span style="font-family:Arial;font-size:10pt;">, the Company owned </span><span style="font-family:Arial;font-size:10pt;"><span>seven</span></span><span style="font-family:Arial;font-size:10pt;"> television stations located in Houston, TX; Detroit, MI; Orlando, FL; San Antonio, TX; Roanoke, VA; and </span><span style="font-family:Arial;font-size:10pt;"><span>two</span></span><span style="font-family:Arial;font-size:10pt;"> stations in Jacksonville, FL. All stations are network-affiliated except for WJXT in Jacksonville, FL.</span></div><div style="line-height:110%;padding-bottom:12px;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;font-weight:bold;">Manufacturing</span><span style="font-family:Arial;font-size:10pt;">—The Company’s manufacturing businesses include Hoover, Dekko, Joyce/Dayton and Forney.</span></div><div style="line-height:110%;padding-bottom:12px;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;font-weight:bold;">Other</span><span style="font-family:Arial;font-size:10pt;">—The Company’s other business operations include automotive dealerships, restaurants and entertainment venues and home health and hospice services.</span></div>
CY2019	us-gaap	Use Of Estimates UseOfEstimates	<div style="line-height:110%;padding-bottom:12px;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;font-weight:bold;">Use of Estimates. </span><span style="font-family:inherit;font-size:10pt;"> </span><span style="font-family:Arial;font-size:10pt;">The preparation of financial statements in conformity with GAAP requires management to make estimates and judgments that affect the amounts reported in the financial statements. Management bases its estimates and assumptions on historical experience and on various other factors that are believed to be reasonable under the circumstances. Due to the inherent uncertainty involved in making estimates, actual results reported in future periods may be affected by changes in those estimates. On an ongoing basis, the Company evaluates its estimates and assumptions.</span></div>
CY2019	us-gaap	Concentration Risk Credit Risk ConcentrationRiskCreditRisk	<div style="line-height:110%;padding-bottom:12px;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;font-weight:bold;">Concentration of Credit Risk. </span><span style="font-family:inherit;font-size:10pt;"> </span><span style="font-family:Arial;font-size:10pt;">Cash and cash equivalents are maintained with several financial institutions domestically and internationally. Deposits held with banks may exceed the amount of insurance provided on such deposits. Generally, these deposits may be redeemed upon demand and are maintained with financial institutions with investment-grade credit ratings. The Company routinely assesses the financial strength of significant customers, and this assessment, combined with the large number and geographical diversity of its customers, limits the Company’s concentration of risk with respect to receivables from contracts with customers.</span></div>
CY2019	ghc	Maximum Termof Contract MaximumTermofContract	P1Y
CY2019Q1	us-gaap	Other Assets Current OtherAssetsCurrent	77128000	USD
CY2019Q1	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	369333000	USD
CY2019Q1	us-gaap	Accounts Payable And Accrued Liabilities Current AccountsPayableAndAccruedLiabilitiesCurrent	472549000	USD
CY2019Q1	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	86747000	USD
CY2019Q1	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	17401000	USD
CY2019Q1	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	331520000	USD
CY2019	us-gaap	Number Of Businesses Acquired NumberOfBusinessesAcquired	8	business
CY2019	us-gaap	Business Combination Consideration Transferred1 BusinessCombinationConsiderationTransferred1	211800000	USD
CY2019Q4	ghc	Vehicle Floor Plan Facility Payable VehicleFloorPlanFacilityPayable	25800000	USD
CY2018	us-gaap	Number Of Businesses Acquired NumberOfBusinessesAcquired	8	business
CY2018	us-gaap	Business Combination Consideration Transferred1 BusinessCombinationConsiderationTransferred1	121100000	USD
CY2017	us-gaap	Number Of Businesses Acquired NumberOfBusinessesAcquired	6	business
CY2017	us-gaap	Business Combination Consideration Transferred1 BusinessCombinationConsiderationTransferred1	318900000	USD
CY2017Q4	ghc	Business Combination Recognized Identifiable Assets Acquiredand Liabilities Assumed Pensionand Other Post Retirement Benefits Liabilities BusinessCombinationRecognizedIdentifiableAssetsAcquiredandLiabilitiesAssumedPensionandOtherPostRetirementBenefitsLiabilities	59100000	USD
CY2019Q4	us-gaap	Business Acquisition Cost Of Acquired Entity Transaction Costs BusinessAcquisitionCostOfAcquiredEntityTransactionCosts	3000000.0	USD
CY2018Q4	us-gaap	Business Acquisition Cost Of Acquired Entity Transaction Costs BusinessAcquisitionCostOfAcquiredEntityTransactionCosts	1500000	USD
CY2017Q4	us-gaap	Business Acquisition Cost Of Acquired Entity Transaction Costs BusinessAcquisitionCostOfAcquiredEntityTransactionCosts	4100000	USD
CY2019Q4	us-gaap	Business Acquisition Purchase Price Allocation Goodwill Expected Tax Deductible Amount BusinessAcquisitionPurchasePriceAllocationGoodwillExpectedTaxDeductibleAmount	70700000	USD
CY2018Q4	us-gaap	Business Acquisition Purchase Price Allocation Goodwill Expected Tax Deductible Amount BusinessAcquisitionPurchasePriceAllocationGoodwillExpectedTaxDeductibleAmount	32300000	USD
CY2017Q4	us-gaap	Business Acquisition Purchase Price Allocation Goodwill Expected Tax Deductible Amount BusinessAcquisitionPurchasePriceAllocationGoodwillExpectedTaxDeductibleAmount	11000000.0	USD
CY2019	us-gaap	Business Combination Pro Forma Information Revenue Of Acquiree Since Acquisition Date Actual BusinessCombinationProFormaInformationRevenueOfAcquireeSinceAcquisitionDateActual	308800000	USD
CY2019	us-gaap	Business Combination Pro Forma Information Earnings Or Loss Of Acquiree Since Acquisition Date Actual BusinessCombinationProFormaInformationEarningsOrLossOfAcquireeSinceAcquisitionDateActual	-5000000.0	USD
CY2019	us-gaap	Business Acquisitions Pro Forma Revenue BusinessAcquisitionsProFormaRevenue	3058872000	USD
CY2018	us-gaap	Business Acquisitions Pro Forma Revenue BusinessAcquisitionsProFormaRevenue	3166907000	USD
CY2017	us-gaap	Business Acquisitions Pro Forma Revenue BusinessAcquisitionsProFormaRevenue	2725046000	USD
CY2019	us-gaap	Business Acquisitions Pro Forma Net Income Loss BusinessAcquisitionsProFormaNetIncomeLoss	326927000	USD
CY2018	us-gaap	Business Acquisitions Pro Forma Net Income Loss BusinessAcquisitionsProFormaNetIncomeLoss	275074000	USD
CY2017	us-gaap	Business Acquisitions Pro Forma Net Income Loss BusinessAcquisitionsProFormaNetIncomeLoss	311397000	USD
CY2019Q4	us-gaap	Money Market Funds At Carrying Value MoneyMarketFundsAtCarryingValue	45200000	USD
CY2018Q4	us-gaap	Money Market Funds At Carrying Value MoneyMarketFundsAtCarryingValue	75500000	USD
CY2019Q4	us-gaap	Equity Securities Fv Ni Cost EquitySecuritiesFvNiCost	282349000	USD
CY2018Q4	us-gaap	Equity Securities Fv Ni Cost EquitySecuritiesFvNiCost	282563000	USD
CY2019Q4	ghc	Equity Securities Fvni Accumulated Gross Unrealized Gain EquitySecuritiesFVNIAccumulatedGrossUnrealizedGain	302731000	USD
CY2018Q4	ghc	Equity Securities Fvni Accumulated Gross Unrealized Gain EquitySecuritiesFVNIAccumulatedGrossUnrealizedGain	216111000	USD
CY2019Q4	ghc	Equity Securities Fvni Accumulated Gross Unrealized Loss EquitySecuritiesFVNIAccumulatedGrossUnrealizedLoss	0	USD
CY2018Q4	ghc	Equity Securities Fvni Accumulated Gross Unrealized Loss EquitySecuritiesFVNIAccumulatedGrossUnrealizedLoss	2284000	USD
CY2019Q4	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	585080000	USD
CY2018Q4	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	496390000	USD
CY2019	us-gaap	Payments To Acquire Marketable Securities PaymentsToAcquireMarketableSecurities	7500000	USD
CY2018	us-gaap	Payments To Acquire Marketable Securities PaymentsToAcquireMarketableSecurities	42700000	USD
CY2017	us-gaap	Payments To Acquire Marketable Securities PaymentsToAcquireMarketableSecurities	0	USD
CY2019	us-gaap	Marketable Securities Realized Gain Loss MarketableSecuritiesRealizedGainLoss	9500000	USD
CY2018	us-gaap	Marketable Securities Realized Gain Loss MarketableSecuritiesRealizedGainLoss	37300000	USD
CY2019	us-gaap	Proceeds From Sale And Maturity Of Marketable Securities ProceedsFromSaleAndMaturityOfMarketableSecurities	19300000	USD
CY2018	us-gaap	Proceeds From Sale And Maturity Of Marketable Securities ProceedsFromSaleAndMaturityOfMarketableSecurities	66700000	USD
CY2017	us-gaap	Proceeds From Sale And Maturity Of Marketable Securities ProceedsFromSaleAndMaturityOfMarketableSecurities	0	USD
CY2019	us-gaap	Equity Securities Fv Ni Gain Loss EquitySecuritiesFvNiGainLoss	98668000	USD
CY2018	us-gaap	Equity Securities Fv Ni Gain Loss EquitySecuritiesFvNiGainLoss	-15843000	USD
CY2019	us-gaap	Equity Securities Fv Ni Realized Gain Loss EquitySecuritiesFvNiRealizedGainLoss	2810000	USD
CY2018	us-gaap	Equity Securities Fv Ni Realized Gain Loss EquitySecuritiesFvNiRealizedGainLoss	-4271000	USD
CY2019	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	95858000	USD
CY2018	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	-11572000	USD
CY2019Q4	us-gaap	Retained Earnings Undistributed Earnings From Equity Method Investees RetainedEarningsUndistributedEarningsFromEquityMethodInvestees	25600000	USD
CY2018Q4	us-gaap	Retained Earnings Undistributed Earnings From Equity Method Investees RetainedEarningsUndistributedEarningsFromEquityMethodInvestees	21200000	USD
CY2017Q4	us-gaap	Equity Method Investment Other Than Temporary Impairment EquityMethodInvestmentOtherThanTemporaryImpairment	2800000	USD
CY2019Q4	us-gaap	Equity Securities Without Readily Determinable Fair Value Amount EquitySecuritiesWithoutReadilyDeterminableFairValueAmount	38500000	USD
CY2018Q4	us-gaap	Equity Securities Without Readily Determinable Fair Value Amount EquitySecuritiesWithoutReadilyDeterminableFairValueAmount	30600000	USD
CY2019	us-gaap	Equity Securities Without Readily Determinable Fair Value Upward Price Adjustment Annual Amount EquitySecuritiesWithoutReadilyDeterminableFairValueUpwardPriceAdjustmentAnnualAmount	5100000	USD
CY2018	us-gaap	Equity Securities Without Readily Determinable Fair Value Upward Price Adjustment Annual Amount EquitySecuritiesWithoutReadilyDeterminableFairValueUpwardPriceAdjustmentAnnualAmount	11700000	USD
CY2018	us-gaap	Equity Securities Without Readily Determinable Fair Value Impairment Loss Annual Amount EquitySecuritiesWithoutReadilyDeterminableFairValueImpairmentLossAnnualAmount	2700000	USD
CY2019Q4	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	595321000	USD
CY2018Q4	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	538021000	USD
CY2019Q4	us-gaap	Other Receivables OtherReceivables	28895000	USD
CY2018Q4	us-gaap	Other Receivables OtherReceivables	44259000	USD
CY2019Q4	us-gaap	Accounts And Other Receivables Net Current AccountsAndOtherReceivablesNetCurrent	624216000	USD
CY2018Q4	us-gaap	Accounts And Other Receivables Net Current AccountsAndOtherReceivablesNetCurrent	582280000	USD
CY2019Q4	us-gaap	Accounts Payable And Other Accrued Liabilities Current AccountsPayableAndOtherAccruedLiabilitiesCurrent	366963000	USD
CY2018Q4	us-gaap	Accounts Payable And Other Accrued Liabilities Current AccountsPayableAndOtherAccruedLiabilitiesCurrent	337123000	USD
CY2019Q4	us-gaap	Employee Related Liabilities Current EmployeeRelatedLiabilitiesCurrent	140738000	USD
CY2018Q4	us-gaap	Employee Related Liabilities Current EmployeeRelatedLiabilitiesCurrent	149455000	USD
CY2019Q4	us-gaap	Accounts Payable And Accrued Liabilities Current AccountsPayableAndAccruedLiabilitiesCurrent	507701000	USD
CY2018Q4	us-gaap	Accounts Payable And Accrued Liabilities Current AccountsPayableAndAccruedLiabilitiesCurrent	486578000	USD
CY2019Q4	us-gaap	Bank Overdrafts BankOverdrafts	500000	USD
CY2018Q4	us-gaap	Bank Overdrafts BankOverdrafts	300000	USD
CY2019Q4	us-gaap	Prepaid Expense Current PrepaidExpenseCurrent	92300000	USD
CY2018Q4	us-gaap	Prepaid Expense Current PrepaidExpenseCurrent	71200000	USD
CY2019Q4	us-gaap	Inventory Raw Materials Net Of Reserves InventoryRawMaterialsNetOfReserves	35119000	USD
CY2018Q4	us-gaap	Inventory Raw Materials Net Of Reserves InventoryRawMaterialsNetOfReserves	37248000	USD
CY2019Q4	us-gaap	Inventory Work In Process Net Of Reserves InventoryWorkInProcessNetOfReserves	10775000	USD
CY2018Q4	us-gaap	Inventory Work In Process Net Of Reserves InventoryWorkInProcessNetOfReserves	11633000	USD
CY2019Q4	us-gaap	Inventory Finished Goods Net Of Reserves InventoryFinishedGoodsNetOfReserves	58696000	USD
CY2018Q4	us-gaap	Inventory Finished Goods Net Of Reserves InventoryFinishedGoodsNetOfReserves	17861000	USD
CY2019Q4	us-gaap	Inventory For Long Term Contracts Or Programs InventoryForLongTermContractsOrPrograms	4338000	USD
CY2018Q4	us-gaap	Inventory For Long Term Contracts Or Programs InventoryForLongTermContractsOrPrograms	2735000	USD
CY2019Q4	us-gaap	Inventory Net Of Allowances Customer Advances And Progress Billings InventoryNetOfAllowancesCustomerAdvancesAndProgressBillings	108928000	USD
CY2018Q4	us-gaap	Inventory Net Of Allowances Customer Advances And Progress Billings InventoryNetOfAllowancesCustomerAdvancesAndProgressBillings	69477000	USD
CY2019Q4	us-gaap	Land Land	17489000	USD
CY2018Q4	us-gaap	Land Land	15965000	USD
CY2019Q4	us-gaap	Buildings And Improvements Gross BuildingsAndImprovementsGross	133189000	USD
CY2018Q4	us-gaap	Buildings And Improvements Gross BuildingsAndImprovementsGross	108683000	USD
CY2019Q4	us-gaap	Machinery And Equipment Gross MachineryAndEquipmentGross	370218000	USD
CY2018Q4	us-gaap	Machinery And Equipment Gross MachineryAndEquipmentGross	382064000	USD
CY2019Q4	us-gaap	Leasehold Improvements Gross LeaseholdImprovementsGross	233842000	USD
CY2018Q4	us-gaap	Leasehold Improvements Gross LeaseholdImprovementsGross	206170000	USD
CY2019Q4	us-gaap	Construction In Progress Gross ConstructionInProgressGross	79963000	USD
CY2018Q4	us-gaap	Construction In Progress Gross ConstructionInProgressGross	68064000	USD
CY2019Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	834701000	USD
CY2018Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	780946000	USD
CY2019Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	450031000	USD
CY2018Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	487861000	USD
CY2019Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	384670000	USD
CY2018Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	293085000	USD
CY2019	us-gaap	Depreciation Depreciation	59300000	USD
CY2018	us-gaap	Depreciation Depreciation	56700000	USD
CY2017	us-gaap	Depreciation Depreciation	62500000	USD
CY2019	us-gaap	Interest Costs Capitalized InterestCostsCapitalized	2100000	USD
CY2018	us-gaap	Interest Costs Capitalized InterestCostsCapitalized	800000	USD
CY2017	us-gaap	Interest Costs Capitalized InterestCostsCapitalized	300000	USD
CY2019	us-gaap	Tangible Asset Impairment Charges TangibleAssetImpairmentCharges	300000	USD
CY2018	us-gaap	Tangible Asset Impairment Charges TangibleAssetImpairmentCharges	200000	USD
CY2017	us-gaap	Tangible Asset Impairment Charges TangibleAssetImpairmentCharges	1000000.0	USD
CY2019	us-gaap	Operating Lease Cost OperatingLeaseCost	104007000	USD
CY2019	ghc	Short Termand Monthto Month Lease Cost ShortTermandMonthtoMonthLeaseCost	19267000	USD
CY2019	us-gaap	Variable Lease Cost VariableLeaseCost	20582000	USD
CY2019	us-gaap	Sublease Income SubleaseIncome	20108000	USD
CY2019	ghc	Lease Cost Netof Sublease Income LeaseCostNetofSubleaseIncome	123748000	USD
CY2019	us-gaap	Operating Lease Impairment Loss OperatingLeaseImpairmentLoss	1100000	USD
CY2019	us-gaap	Operating Lease Payments OperatingLeasePayments	112671000	USD
CY2019	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	236714000	USD
CY2019Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	526417000	USD
CY2019Q4	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	92714000	USD
CY2019Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	477004000	USD
CY2019Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	569718000	USD
CY2019Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P10Y6M
CY2019Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.043
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due Next Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	115112000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	98530000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	80255000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	65024000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	51731000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	322674000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	733326000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	163608000	USD
CY2019Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	569718000	USD
CY2019Q4	ghc	Lessee Operating Lease Lease Notyet Commenced Payments Due LesseeOperatingLeaseLeaseNotyetCommencedPaymentsDue	17200000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due Current OperatingLeasesFutureMinimumPaymentsDueCurrent	101009000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due In Two Years OperatingLeasesFutureMinimumPaymentsDueInTwoYears	84945000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due In Three Years OperatingLeasesFutureMinimumPaymentsDueInThreeYears	72031000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due In Four Years OperatingLeasesFutureMinimumPaymentsDueInFourYears	53709000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due In Five Years OperatingLeasesFutureMinimumPaymentsDueInFiveYears	47091000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due Thereafter OperatingLeasesFutureMinimumPaymentsDueThereafter	115948000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due OperatingLeasesFutureMinimumPaymentsDue	474733000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due Future Minimum Sublease Rentals OperatingLeasesFutureMinimumPaymentsDueFutureMinimumSubleaseRentals	66000000.0	USD
CY2018	us-gaap	Lease And Rental Expense LeaseAndRentalExpense	83400000	USD
CY2017	us-gaap	Lease And Rental Expense LeaseAndRentalExpense	81100000	USD
CY2018	us-gaap	Operating Leases Income Statement Sublease Revenue OperatingLeasesIncomeStatementSubleaseRevenue	15600000	USD
CY2017	us-gaap	Operating Leases Income Statement Sublease Revenue OperatingLeasesIncomeStatementSubleaseRevenue	14800000	USD
CY2019	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	8	Segment
CY2019	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	53200000	USD
CY2018	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	47400000	USD
CY2017	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	41200000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Next Twelve Months FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths	53000000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Two FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo	47000000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Three FiniteLivedIntangibleAssetsAmortizationExpenseYearThree	41000000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Four FiniteLivedIntangibleAssetsAmortizationExpenseYearFour	34000000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Five FiniteLivedIntangibleAssetsAmortizationExpenseYearFive	24000000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense After Year Five FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFive	34000000	USD
CY2017Q4	us-gaap	Goodwill Gross GoodwillGross	1665861000	USD
CY2017Q4	us-gaap	Goodwill Impaired Accumulated Impairment Loss GoodwillImpairedAccumulatedImpairmentLoss	366151000	USD
CY2017Q4	us-gaap	Goodwill Goodwill	1299710000	USD
CY2018	us-gaap	Goodwill Acquired During Period GoodwillAcquiredDuringPeriod	41840000	USD
CY2018	us-gaap	Goodwill Written Off Related To Sale Of Business Unit GoodwillWrittenOffRelatedToSaleOfBusinessUnit	11191000	USD
CY2018	us-gaap	Goodwill Foreign Currency Translation Gain Loss GoodwillForeignCurrencyTranslationGainLoss	-32647000	USD
CY2018Q4	us-gaap	Goodwill Gross GoodwillGross	1644164000	USD
CY2018Q4	us-gaap	Goodwill Impaired Accumulated Impairment Loss GoodwillImpairedAccumulatedImpairmentLoss	346452000	USD
CY2018Q4	us-gaap	Goodwill Goodwill	1297712000	USD
CY2019	us-gaap	Goodwill Acquired During Period GoodwillAcquiredDuringPeriod	84515000	USD
CY2018Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	263261000	USD
CY2019	us-gaap	Goodwill Written Off Related To Sale Of Business Unit GoodwillWrittenOffRelatedToSaleOfBusinessUnit	579000	USD
CY2019	us-gaap	Goodwill Foreign Currency Translation Gain Loss GoodwillForeignCurrencyTranslationGainLoss	6631000	USD
CY2019Q4	us-gaap	Goodwill Gross GoodwillGross	1734731000	USD
CY2019Q4	us-gaap	Goodwill Impaired Accumulated Impairment Loss GoodwillImpairedAccumulatedImpairmentLoss	346452000	USD
CY2019Q4	us-gaap	Goodwill Goodwill	1388279000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	452952000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	219471000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	233481000	USD
CY2018Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	440105000	USD
CY2018Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	176844000	USD
CY2019Q4	us-gaap	Indefinite Lived Intangible Assets Excluding Goodwill IndefiniteLivedIntangibleAssetsExcludingGoodwill	140197000	USD
CY2018Q4	us-gaap	Indefinite Lived Intangible Assets Excluding Goodwill IndefiniteLivedIntangibleAssetsExcludingGoodwill	99052000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	390144000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	257312000	USD
CY2017	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	134276000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	36335000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	66196000	USD
CY2017	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	48513000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	426479000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	323508000	USD
CY2017	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	182789000	USD
CY2019	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	16500000	USD
CY2019	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	63838000	USD
CY2019	us-gaap	Federal Income Tax Expense Benefit Continuing Operations FederalIncomeTaxExpenseBenefitContinuingOperations	80338000	USD
CY2019	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	2949000	USD
CY2019	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	6630000	USD
CY2019	us-gaap	State And Local Income Tax Expense Benefit Continuing Operations StateAndLocalIncomeTaxExpenseBenefitContinuingOperations	9579000	USD
CY2019	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	9400000	USD
CY2019	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	-717000	USD
CY2019	us-gaap	Foreign Income Tax Expense Benefit Continuing Operations ForeignIncomeTaxExpenseBenefitContinuingOperations	8683000	USD
CY2019	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	28849000	USD
CY2019	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	69751000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	98600000	USD
CY2018	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	46059000	USD
CY2018	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	16718000	USD
CY2018	us-gaap	Federal Income Tax Expense Benefit Continuing Operations FederalIncomeTaxExpenseBenefitContinuingOperations	62777000	USD
CY2018	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	2240000	USD
CY2018	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-23809000	USD
CY2018	us-gaap	State And Local Income Tax Expense Benefit Continuing Operations StateAndLocalIncomeTaxExpenseBenefitContinuingOperations	-21569000	USD
CY2018	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	10924000	USD
CY2018	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	-32000	USD
CY2018	us-gaap	Foreign Income Tax Expense Benefit Continuing Operations ForeignIncomeTaxExpenseBenefitContinuingOperations	10892000	USD
CY2018	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	59223000	USD
CY2018	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-7123000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	52100000	USD
CY2017	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	10743000	USD
CY2017	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-153217000	USD
CY2017	us-gaap	Federal Income Tax Expense Benefit Continuing Operations FederalIncomeTaxExpenseBenefitContinuingOperations	-142474000	USD
CY2017	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	5930000	USD
CY2017	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	3306000	USD
CY2017	us-gaap	State And Local Income Tax Expense Benefit Continuing Operations StateAndLocalIncomeTaxExpenseBenefitContinuingOperations	9236000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Undistributed Foreign Earnings DeferredTaxLiabilitiesUndistributedForeignEarnings	1700000	USD
CY2017	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	10079000	USD
CY2017	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	3459000	USD
CY2017	us-gaap	Foreign Income Tax Expense Benefit Continuing Operations ForeignIncomeTaxExpenseBenefitContinuingOperations	13538000	USD
CY2017	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	26752000	USD
CY2017	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-146452000	USD
CY2017	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-119700000	USD
CY2019	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	89561000	USD
CY2018	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	67937000	USD
CY2017	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	63976000	USD
CY2019	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	-4064000	USD
CY2018	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	-1279000	USD
CY2017	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	6949000	USD
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Share Based Compensation Excess Tax Benefit Amount EffectiveIncomeTaxRateReconciliationShareBasedCompensationExcessTaxBenefitAmount	-1743000	USD
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Share Based Compensation Excess Tax Benefit Amount EffectiveIncomeTaxRateReconciliationShareBasedCompensationExcessTaxBenefitAmount	-1731000	USD
CY2017	us-gaap	Effective Income Tax Rate Reconciliation Share Based Compensation Excess Tax Benefit Amount EffectiveIncomeTaxRateReconciliationShareBasedCompensationExcessTaxBenefitAmount	-6023000	USD
CY2019	us-gaap	Income Tax Reconciliation Deductions Qualified Production Activities IncomeTaxReconciliationDeductionsQualifiedProductionActivities	0	USD
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CY2017	us-gaap	Income Tax Reconciliation Deductions Qualified Production Activities IncomeTaxReconciliationDeductionsQualifiedProductionActivities	1329000	USD
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CY2018	us-gaap	Effective Income Tax Rate Reconciliation Tax Cuts And Jobs Act Of2017 Amount EffectiveIncomeTaxRateReconciliationTaxCutsAndJobsActOf2017Amount	0	USD
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CY2019	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	2012000	USD
CY2018	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	1618000	USD
CY2017	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	1268000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	98600000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	52100000	USD
CY2017	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-119700000	USD
CY2017Q4	us-gaap	Tax Cuts And Jobs Act Of2017 Change In Tax Rate Deferred Tax Liability Income Tax Benefit TaxCutsAndJobsActOf2017ChangeInTaxRateDeferredTaxLiabilityIncomeTaxBenefit	153300000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefits	69013000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefits	68392000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Allowance For Doubtful Accounts DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAllowanceForDoubtfulAccounts	3545000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Allowance For Doubtful Accounts DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAllowanceForDoubtfulAccounts	4449000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards State And Local DeferredTaxAssetsOperatingLossCarryforwardsStateAndLocal	51608000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards State And Local DeferredTaxAssetsOperatingLossCarryforwardsStateAndLocal	34107000	USD
CY2017Q4	us-gaap	Tax Cuts And Jobs Act Of2017 Decrease In Deferred Tax Liability Due To Transition Tax TaxCutsAndJobsActOf2017DecreaseInDeferredTaxLiabilityDueToTransitionTax	28300000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards Domestic DeferredTaxAssetsOperatingLossCarryforwardsDomestic	1765000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards Domestic DeferredTaxAssetsOperatingLossCarryforwardsDomestic	2100000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards Foreign DeferredTaxAssetsOperatingLossCarryforwardsForeign	15214000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards Foreign DeferredTaxAssetsOperatingLossCarryforwardsForeign	15868000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Deferred Rent DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsDeferredRent	84923000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Deferred Rent DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsDeferredRent	0	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Other DeferredTaxAssetsTaxDeferredExpenseOther	6003000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Other DeferredTaxAssetsTaxDeferredExpenseOther	14657000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	236678000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	145262000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	46243000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	33120000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	190435000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	112142000	USD
CY2019Q4	ghc	Deferred Tax Liabilities Unrealized Gainson Availableforsale Securities DeferredTaxLiabilitiesUnrealizedGainsonAvailableforsaleSecurities	75709000	USD
CY2018Q4	ghc	Deferred Tax Liabilities Unrealized Gainson Availableforsale Securities DeferredTaxLiabilitiesUnrealizedGainsonAvailableforsaleSecurities	51242000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Goodwill And Intangible Assets DeferredTaxLiabilitiesGoodwillAndIntangibleAssets	92233000	USD
CY2018Q4	us-gaap	Deferred Tax Liabilities Goodwill And Intangible Assets DeferredTaxLiabilitiesGoodwillAndIntangibleAssets	88798000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	16303000	USD
CY2018Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	9997000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Leasing Arrangements DeferredTaxLiabilitiesLeasingArrangements	74407000	USD
CY2018Q4	us-gaap	Deferred Tax Liabilities Leasing Arrangements DeferredTaxLiabilitiesLeasingArrangements	0	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Undistributed Foreign Earnings DeferredTaxLiabilitiesUndistributedForeignEarnings	1670000	USD
CY2018Q4	us-gaap	Deferred Tax Liabilities Undistributed Foreign Earnings DeferredTaxLiabilitiesUndistributedForeignEarnings	1726000	USD
CY2019Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	606178000	USD
CY2018Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	421175000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	415743000	USD
CY2018Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	309033000	USD
CY2018Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	2483000	USD
CY2017Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	17331000	USD
CY2016Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	17331000	USD
CY2019	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	0	USD
CY2018	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	0	USD
CY2017	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	0	USD
CY2019	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	1072000	USD
CY2018	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	500000	USD
CY2017	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	0	USD
CY2019	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	0	USD
CY2018	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	12187000	USD
CY2017	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	0	USD
CY2019	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Settlements With Taxing Authorities UnrecognizedTaxBenefitsDecreasesResultingFromSettlementsWithTaxingAuthorities	1291000	USD
CY2018	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Settlements With Taxing Authorities UnrecognizedTaxBenefitsDecreasesResultingFromSettlementsWithTaxingAuthorities	0	USD
CY2017	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Settlements With Taxing Authorities UnrecognizedTaxBenefitsDecreasesResultingFromSettlementsWithTaxingAuthorities	0	USD
CY2019	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations	692000	USD
CY2018	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations	3161000	USD
CY2017	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations	0	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	1572000	USD
CY2018Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	2483000	USD
CY2017Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	17331000	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits Interest On Income Taxes Accrued UnrecognizedTaxBenefitsInterestOnIncomeTaxesAccrued	800000	USD
CY2019Q4	us-gaap	Other Long Term Debt OtherLongTermDebt	83000	USD
CY2018Q4	us-gaap	Other Long Term Debt OtherLongTermDebt	96000	USD
CY2019Q4	us-gaap	Debt Longterm And Shortterm Combined Amount DebtLongtermAndShorttermCombinedAmount	512829000	USD
CY2018Q4	us-gaap	Debt Longterm And Shortterm Combined Amount DebtLongtermAndShorttermCombinedAmount	477137000	USD
CY2019Q4	us-gaap	Debt Current DebtCurrent	82179000	USD
CY2018Q4	us-gaap	Debt Current DebtCurrent	6360000	USD
CY2019Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	430650000	USD
CY2018Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	470777000	USD
CY2019Q4	us-gaap	Line Of Credit LineOfCredit	0	USD
CY2019	ghc	Average Outstanding Debt Amount AverageOutstandingDebtAmount	500600000	USD
CY2018	ghc	Average Outstanding Debt Amount AverageOutstandingDebtAmount	517200000	USD
CY2019	us-gaap	Debt Instrument Interest Rate During Period DebtInstrumentInterestRateDuringPeriod	0.051
CY2018	us-gaap	Debt Instrument Interest Rate During Period DebtInstrumentInterestRateDuringPeriod	0.056
CY2019	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	-23600000	USD
CY2018	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	-32500000	USD
CY2017	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	-27300000	USD
CY2019	us-gaap	Equity Securities Without Readily Determinable Fair Value Upward Price Adjustment Annual Amount EquitySecuritiesWithoutReadilyDeterminableFairValueUpwardPriceAdjustmentAnnualAmount	5100000	USD
CY2018	us-gaap	Equity Securities Without Readily Determinable Fair Value Upward Price Adjustment Annual Amount EquitySecuritiesWithoutReadilyDeterminableFairValueUpwardPriceAdjustmentAnnualAmount	11700000	USD
CY2019	us-gaap	Asset Impairment Charges AssetImpairmentCharges	9200000	USD
CY2018	us-gaap	Asset Impairment Charges AssetImpairmentCharges	8100000	USD
CY2017	us-gaap	Asset Impairment Charges AssetImpairmentCharges	9600000	USD
CY2019Q4	us-gaap	Deferred Revenue DeferredRevenue	359048000	USD
CY2018Q4	us-gaap	Deferred Revenue DeferredRevenue	311214000	USD
CY2019	ghc	Deferred Revenue Period Increase Decrease Percentage DeferredRevenuePeriodIncreaseDecreasePercentage	0.15
CY2019	us-gaap	Deferred Revenue Revenue Recognized1 DeferredRevenueRevenueRecognized1	281700000	USD
CY2018Q4	us-gaap	Capitalized Contract Cost Net CapitalizedContractCostNet	21311000	USD
CY2019	ghc	Contract Costs Capitalized Duringthe Period ContractCostsCapitalizedDuringthePeriod	66607000	USD
CY2019	us-gaap	Capitalized Contract Cost Amortization CapitalizedContractCostAmortization	-57741000	USD
CY2019	ghc	Changein Capitalized Contract Cost Other ChangeinCapitalizedContractCostOther	843000	USD
CY2019Q4	us-gaap	Capitalized Contract Cost Net CapitalizedContractCostNet	31020000	USD
CY2017Q4	us-gaap	Capitalized Contract Cost Net CapitalizedContractCostNet	16043000	USD
CY2018	ghc	Contract Costs Capitalized Duringthe Period ContractCostsCapitalizedDuringthePeriod	55664000	USD
CY2018	us-gaap	Capitalized Contract Cost Amortization CapitalizedContractCostAmortization	-49284000	USD
CY2018	ghc	Changein Capitalized Contract Cost Other ChangeinCapitalizedContractCostOther	-1112000	USD
CY2018Q4	us-gaap	Capitalized Contract Cost Net CapitalizedContractCostNet	21311000	USD
CY2018Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Number ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber	32200	shares
CY2018Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue	747.18
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Grants In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod	16802	shares
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Grants In Period Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue	639.98
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod	15987	shares
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue	898.85
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Forfeited In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod	3875	shares
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Forfeitures Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue	879.98
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Number ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber	29140	shares
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue	584.50
CY2018Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	184932	shares
CY2018Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	566.55
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Gross ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross	0	shares
CY2019	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Grants In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice	0
CY2019	us-gaap	Stock Issued During Period Shares Stock Options Exercised StockIssuedDuringPeriodSharesStockOptionsExercised	1743	shares
CY2019	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Exercises In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice	276.18
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures And Expirations In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod	0	shares
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures And Expirations In Period Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriodWeightedAverageExercisePrice	0
CY2017	ghc	Undistributed Earnings Allocated To Common Stockholders UndistributedEarningsAllocatedToCommonStockholders	271150000	USD
CY2019	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	29387000	USD
CY2018	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	28423000	USD
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	569.31
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber	160728	shares
CY2019	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Exercisable Weighted Average Remaining Contractual Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1	P3Y2M12D
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice	539.76
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	183189	shares
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	569.31
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	183189	shares
CY2019	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Outstanding Weighted Average Remaining Contractual Term2 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2	P3Y4M24D
CY2017	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Fair Value Assumptions Expected Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1	P8Y
CY2017	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Risk Free Interest Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate	0.0228
CY2017	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Volatility Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate	0.2693
CY2017	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Dividend Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate	0.0085
CY2019	us-gaap	Net Income Loss NetIncomeLoss	327855000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	271206000	USD
CY2017	us-gaap	Net Income Loss NetIncomeLoss	302044000	USD
CY2019	ghc	Dividends Paid Common Stock And Sharebased Compensation Cash DividendsPaidCommonStockAndSharebasedCompensationCash	29553000	USD
CY2018	ghc	Dividends Paid Common Stock And Sharebased Compensation Cash DividendsPaidCommonStockAndSharebasedCompensationCash	28617000	USD
CY2017	ghc	Dividends Paid Common Stock And Sharebased Compensation Cash DividendsPaidCommonStockAndSharebasedCompensationCash	28329000	USD
CY2019	us-gaap	Undistributed Earnings UndistributedEarnings	298302000	USD
CY2018	us-gaap	Undistributed Earnings UndistributedEarnings	242589000	USD
CY2017	us-gaap	Undistributed Earnings UndistributedEarnings	273715000	USD
CY2019	ghc	Percentage Of Undistributed Earnings Allocated To Common Stockholders PercentageOfUndistributedEarningsAllocatedToCommonStockholders	0.9945
CY2018	ghc	Percentage Of Undistributed Earnings Allocated To Common Stockholders PercentageOfUndistributedEarningsAllocatedToCommonStockholders	0.9939
CY2017	ghc	Percentage Of Undistributed Earnings Allocated To Common Stockholders PercentageOfUndistributedEarningsAllocatedToCommonStockholders	0.9906
CY2019	ghc	Undistributed Earnings Allocated To Common Stockholders UndistributedEarningsAllocatedToCommonStockholders	296665000	USD
CY2018	ghc	Undistributed Earnings Allocated To Common Stockholders UndistributedEarningsAllocatedToCommonStockholders	241115000	USD
CY2017	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	28060000	USD
CY2019	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	326052000	USD
CY2018	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	269538000	USD
CY2017	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	299210000	USD
CY2019	ghc	Additional Undistributed Earnings Due To Dilutive Stock Options AdditionalUndistributedEarningsDueToDilutiveStockOptions	13000	USD
CY2018	ghc	Additional Undistributed Earnings Due To Dilutive Stock Options AdditionalUndistributedEarningsDueToDilutiveStockOptions	10000	USD
CY2017	ghc	Additional Undistributed Earnings Due To Dilutive Stock Options AdditionalUndistributedEarningsDueToDilutiveStockOptions	17000	USD
CY2019	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	326065000	USD
CY2018	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	269548000	USD
CY2017	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	299227000	USD
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	5285000	shares
CY2018	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	5333000	shares
CY2017	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	5516000	shares
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	5327000	shares
CY2018	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	5370000	shares
CY2017	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	5552000	shares
CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	61.70
CY2018	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	50.55
CY2017	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	54.24
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	61.21
CY2018	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	50.20
CY2017	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	53.89
CY2019	ghc	Antidilutive Restricted Stock AntidilutiveRestrictedStock	12000	shares
CY2018	ghc	Antidilutive Restricted Stock AntidilutiveRestrictedStock	23000	shares
CY2017	ghc	Antidilutive Restricted Stock AntidilutiveRestrictedStock	30000	shares
CY2019	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	5.56
CY2018	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	5.32
CY2017	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	5.08
CY2019	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	9800000	USD
CY2018	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	8600000	USD
CY2017	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	7500000	USD
CY2019	ghc	Losson Guarantor Lease Obligations LossonGuarantorLeaseObligations	1075000	USD
CY2019	us-gaap	Equity Securities Without Readily Determinable Fair Value Upward Price Adjustment Annual Amount EquitySecuritiesWithoutReadilyDeterminableFairValueUpwardPriceAdjustmentAnnualAmount	5080000	USD
CY2019	us-gaap	Equity Method Investment Realized Gain Loss On Disposal EquityMethodInvestmentRealizedGainLossOnDisposal	28994000	USD
CY2018	us-gaap	Equity Method Investment Realized Gain Loss On Disposal EquityMethodInvestmentRealizedGainLossOnDisposal	0	USD
CY2017	us-gaap	Equity Method Investment Realized Gain Loss On Disposal EquityMethodInvestmentRealizedGainLossOnDisposal	0	USD
CY2018	ghc	Losson Guarantor Lease Obligations LossonGuarantorLeaseObligations	17518000	USD
CY2017	ghc	Losson Guarantor Lease Obligations LossonGuarantorLeaseObligations	0	USD
CY2018	us-gaap	Equity Securities Without Readily Determinable Fair Value Upward Price Adjustment Annual Amount EquitySecuritiesWithoutReadilyDeterminableFairValueUpwardPriceAdjustmentAnnualAmount	11663000	USD
CY2017	us-gaap	Equity Securities Without Readily Determinable Fair Value Upward Price Adjustment Annual Amount EquitySecuritiesWithoutReadilyDeterminableFairValueUpwardPriceAdjustmentAnnualAmount	0	USD
CY2019	us-gaap	Gain Loss On Sale Of Business GainLossOnSaleOfBusiness	-564000	USD
CY2018	us-gaap	Gain Loss On Sale Of Business GainLossOnSaleOfBusiness	8157000	USD
CY2017	us-gaap	Gain Loss On Sale Of Business GainLossOnSaleOfBusiness	-569000	USD
CY2019	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	-1070000	USD
CY2018	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	-3844000	USD
CY2017	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	3310000	USD
CY2019	us-gaap	Cost Method Investments Realized Gain Loss CostMethodInvestmentsRealizedGainLoss	267000	USD
CY2018	us-gaap	Cost Method Investments Realized Gain Loss CostMethodInvestmentsRealizedGainLoss	2845000	USD
CY2017	us-gaap	Cost Method Investments Realized Gain Loss CostMethodInvestmentsRealizedGainLoss	16000	USD
CY2019	us-gaap	Equity Securities Without Readily Determinable Fair Value Impairment Loss Annual Amount EquitySecuritiesWithoutReadilyDeterminableFairValueImpairmentLossAnnualAmount	0	USD
CY2018	us-gaap	Equity Securities Without Readily Determinable Fair Value Impairment Loss Annual Amount EquitySecuritiesWithoutReadilyDeterminableFairValueImpairmentLossAnnualAmount	2697000	USD
CY2017	us-gaap	Costmethod Investments Other Than Temporary Impairment CostmethodInvestmentsOtherThanTemporaryImpairment	200000	USD
CY2019	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	-82000	USD
CY2018	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	2539000	USD
CY2017	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	0	USD
CY2019	us-gaap	Other Nonoperating Gains Losses OtherNonoperatingGainsLosses	881000	USD
CY2018	us-gaap	Other Nonoperating Gains Losses OtherNonoperatingGainsLosses	958000	USD
CY2017	us-gaap	Other Nonoperating Gains Losses OtherNonoperatingGainsLosses	1684000	USD
CY2019	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	32431000	USD
CY2018	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	2103000	USD
CY2017	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	4241000	USD
CY2019Q1	us-gaap	Equity Securities Without Readily Determinable Fair Value Upward Price Adjustment Annual Amount EquitySecuritiesWithoutReadilyDeterminableFairValueUpwardPriceAdjustmentAnnualAmount	1300000	USD
CY2019Q3	us-gaap	Equity Securities Without Readily Determinable Fair Value Upward Price Adjustment Annual Amount EquitySecuritiesWithoutReadilyDeterminableFairValueUpwardPriceAdjustmentAnnualAmount	3700000	USD
CY2018Q3	us-gaap	Equity Securities Without Readily Determinable Fair Value Upward Price Adjustment Annual Amount EquitySecuritiesWithoutReadilyDeterminableFairValueUpwardPriceAdjustmentAnnualAmount	8500000	USD
CY2018Q4	us-gaap	Equity Securities Without Readily Determinable Fair Value Upward Price Adjustment Annual Amount EquitySecuritiesWithoutReadilyDeterminableFairValueUpwardPriceAdjustmentAnnualAmount	3200000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	133553000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	34087000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	99466000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	-174347000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	-37510000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-136837000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	319059000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	90923000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	228136000	USD
CY2018	ghc	Reclassification From Accumulated Other Comprehensive Income To Retained Earnings ReclassificationFromAccumulatedOtherComprehensiveIncomeToRetainedEarnings	194889000	USD
CY2019Q4	us-gaap	Loss Contingency Pending Claims Number LossContingencyPendingClaimsNumber	0	claim
CY2019	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	8	Segment
CY2019	us-gaap	Revenues Revenues	2932099000	USD
CY2018	us-gaap	Revenues Revenues	2695966000	USD
CY2017	us-gaap	Revenues Revenues	2591846000	USD
CY2019	us-gaap	Operating Income Loss OperatingIncomeLoss	144546000	USD
CY2018	us-gaap	Operating Income Loss OperatingIncomeLoss	246161000	USD
CY2017	us-gaap	Operating Income Loss OperatingIncomeLoss	136403000	USD
CY2019	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	11664000	USD
CY2018	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	14473000	USD
CY2017	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	-3249000	USD
CY2019	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	-23628000	USD
CY2018	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	-32549000	USD
CY2017	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	-27305000	USD
CY2019	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	0	USD
CY2018	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	-11378000	USD
CY2017	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	0	USD
CY2019	us-gaap	Net Periodic Defined Benefits Expense Reversal Of Expense Excluding Service Cost Component NetPeriodicDefinedBenefitsExpenseReversalOfExpenseExcludingServiceCostComponent	-162798000	USD
CY2018	us-gaap	Net Periodic Defined Benefits Expense Reversal Of Expense Excluding Service Cost Component NetPeriodicDefinedBenefitsExpenseReversalOfExpenseExcludingServiceCostComponent	-120541000	USD
CY2017	us-gaap	Net Periodic Defined Benefits Expense Reversal Of Expense Excluding Service Cost Component NetPeriodicDefinedBenefitsExpenseReversalOfExpenseExcludingServiceCostComponent	-72699000	USD
CY2019	us-gaap	Equity Securities Fv Ni Gain Loss EquitySecuritiesFvNiGainLoss	98668000	USD
CY2018	us-gaap	Equity Securities Fv Ni Gain Loss EquitySecuritiesFvNiGainLoss	-15843000	USD
CY2017	us-gaap	Equity Securities Fv Ni Gain Loss EquitySecuritiesFvNiGainLoss	0	USD
CY2019	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	32431000	USD
CY2018	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	2103000	USD
CY2017	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	4241000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	426479000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	323508000	USD
CY2017	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	182789000	USD
CY2019	us-gaap	Depreciation Depreciation	59253000	USD
CY2018	us-gaap	Depreciation Depreciation	56722000	USD
CY2017	us-gaap	Depreciation Depreciation	62509000	USD
CY2019	ghc	Amortization Of Intangible Assets And Impairment Of Goodwill And Other Long Lived Assets AmortizationOfIntangibleAssetsAndImpairmentOfGoodwillAndOtherLongLivedAssets	62395000	USD
CY2018	ghc	Amortization Of Intangible Assets And Impairment Of Goodwill And Other Long Lived Assets AmortizationOfIntangibleAssetsAndImpairmentOfGoodwillAndOtherLongLivedAssets	55523000	USD
CY2017	ghc	Amortization Of Intangible Assets And Impairment Of Goodwill And Other Long Lived Assets AmortizationOfIntangibleAssetsAndImpairmentOfGoodwillAndOtherLongLivedAssets	50801000	USD
CY2019	us-gaap	Defined Benefit Plan Net Periodic Benefit Cost DefinedBenefitPlanNetPeriodicBenefitCost	20422000	USD
CY2018	us-gaap	Defined Benefit Plan Net Periodic Benefit Cost DefinedBenefitPlanNetPeriodicBenefitCost	18221000	USD
CY2017	us-gaap	Defined Benefit Plan Net Periodic Benefit Cost DefinedBenefitPlanNetPeriodicBenefitCost	18687000	USD
CY2019	us-gaap	Property Plant And Equipment Additions PropertyPlantAndEquipmentAdditions	93947000	USD
CY2018	us-gaap	Property Plant And Equipment Additions PropertyPlantAndEquipmentAdditions	98067000	USD
CY2017	us-gaap	Property Plant And Equipment Additions PropertyPlantAndEquipmentAdditions	57080000	USD
CY2019Q4	ghc	Identifiable Assets IdentifiableAssets	3891557000	USD
CY2018Q4	ghc	Identifiable Assets IdentifiableAssets	3120280000	USD
CY2019Q4	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	585080000	USD
CY2018Q4	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	496390000	USD
CY2019Q4	us-gaap	Investments In Affiliates Subsidiaries Associates And Joint Ventures InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures	162249000	USD
CY2018Q4	us-gaap	Investments In Affiliates Subsidiaries Associates And Joint Ventures InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures	143813000	USD
CY2019Q4	us-gaap	Defined Benefit Plan Assets For Plan Benefits Noncurrent DefinedBenefitPlanAssetsForPlanBenefitsNoncurrent	1292350000	USD
CY2018Q4	us-gaap	Defined Benefit Plan Assets For Plan Benefits Noncurrent DefinedBenefitPlanAssetsForPlanBenefitsNoncurrent	1003558000	USD
CY2019Q4	us-gaap	Assets Assets	5931236000	USD
CY2018Q4	us-gaap	Assets Assets	4764041000	USD
CY2019Q1	us-gaap	Revenues Revenues	692199000	USD
CY2019Q2	us-gaap	Revenues Revenues	737602000	USD
CY2019Q3	us-gaap	Revenues Revenues	738820000	USD
CY2019Q4	us-gaap	Revenues Revenues	763478000	USD
CY2019Q1	ghc	Operating Expense OperatingExpense	477230000	USD
CY2019Q2	ghc	Operating Expense OperatingExpense	503763000	USD
CY2019Q1	us-gaap	Asset Impairment Charges AssetImpairmentCharges	0	USD
CY2019Q2	us-gaap	Asset Impairment Charges AssetImpairmentCharges	693000	USD
CY2019Q3	ghc	Operating Expense OperatingExpense	517935000	USD
CY2019Q4	ghc	Operating Expense OperatingExpense	524277000	USD
CY2019Q1	ghc	Selling Generaland Administrative Expenses SellingGeneralandAdministrativeExpenses	148383000	USD
CY2019Q2	ghc	Selling Generaland Administrative Expenses SellingGeneralandAdministrativeExpenses	148419000	USD
CY2019Q3	ghc	Selling Generaland Administrative Expenses SellingGeneralandAdministrativeExpenses	175322000	USD
CY2019Q4	ghc	Selling Generaland Administrative Expenses SellingGeneralandAdministrativeExpenses	170576000	USD
CY2019Q1	us-gaap	Depreciation Depreciation	13523000	USD
CY2019Q2	us-gaap	Depreciation Depreciation	13884000	USD
CY2019Q3	us-gaap	Depreciation Depreciation	15351000	USD
CY2019Q4	us-gaap	Depreciation Depreciation	16495000	USD
CY2019Q1	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	13060000	USD
CY2019Q2	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	12880000	USD
CY2019Q3	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	13572000	USD
CY2019Q4	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	13731000	USD
CY2019Q3	us-gaap	Asset Impairment Charges AssetImpairmentCharges	372000	USD
CY2019Q4	us-gaap	Asset Impairment Charges AssetImpairmentCharges	8087000	USD
CY2019Q1	us-gaap	Costs And Expenses CostsAndExpenses	652196000	USD
CY2019Q2	us-gaap	Costs And Expenses CostsAndExpenses	679639000	USD
CY2019Q3	us-gaap	Costs And Expenses CostsAndExpenses	722552000	USD
CY2019Q4	us-gaap	Costs And Expenses CostsAndExpenses	733166000	USD
CY2019Q1	us-gaap	Operating Income Loss OperatingIncomeLoss	40003000	USD
CY2019Q2	us-gaap	Operating Income Loss OperatingIncomeLoss	57963000	USD
CY2019Q3	us-gaap	Operating Income Loss OperatingIncomeLoss	16268000	USD
CY2019Q4	us-gaap	Operating Income Loss OperatingIncomeLoss	30312000	USD
CY2019Q1	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	1679000	USD
CY2019Q2	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	1467000	USD
CY2019Q3	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	4683000	USD
CY2019Q4	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	3835000	USD
CY2019Q1	us-gaap	Investment Income Interest InvestmentIncomeInterest	1700000	USD
CY2019Q2	us-gaap	Investment Income Interest InvestmentIncomeInterest	1579000	USD
CY2019Q3	us-gaap	Investment Income Interest InvestmentIncomeInterest	1474000	USD
CY2019Q4	us-gaap	Investment Income Interest InvestmentIncomeInterest	1398000	USD
CY2019Q1	us-gaap	Interest Expense InterestExpense	7425000	USD
CY2019Q2	us-gaap	Interest Expense InterestExpense	8386000	USD
CY2019Q3	us-gaap	Interest Expense InterestExpense	6776000	USD
CY2019Q4	us-gaap	Interest Expense InterestExpense	7192000	USD
CY2019Q1	us-gaap	Net Periodic Defined Benefits Expense Reversal Of Expense Excluding Service Cost Component NetPeriodicDefinedBenefitsExpenseReversalOfExpenseExcludingServiceCostComponent	-19928000	USD
CY2019Q2	us-gaap	Net Periodic Defined Benefits Expense Reversal Of Expense Excluding Service Cost Component NetPeriodicDefinedBenefitsExpenseReversalOfExpenseExcludingServiceCostComponent	-12253000	USD
CY2019Q4	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	-3704000	USD
CY2019Q1	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	109302000	USD
CY2019Q2	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	16700000	USD
CY2019Q3	us-gaap	Net Periodic Defined Benefits Expense Reversal Of Expense Excluding Service Cost Component NetPeriodicDefinedBenefitsExpenseReversalOfExpenseExcludingServiceCostComponent	-19556000	USD
CY2019Q4	us-gaap	Net Periodic Defined Benefits Expense Reversal Of Expense Excluding Service Cost Component NetPeriodicDefinedBenefitsExpenseReversalOfExpenseExcludingServiceCostComponent	-111061000	USD
CY2019Q1	us-gaap	Equity Securities Fv Ni Gain Loss EquitySecuritiesFvNiGainLoss	24066000	USD
CY2019Q2	us-gaap	Equity Securities Fv Ni Gain Loss EquitySecuritiesFvNiGainLoss	7791000	USD
CY2019Q3	us-gaap	Equity Securities Fv Ni Gain Loss EquitySecuritiesFvNiGainLoss	17404000	USD
CY2019Q4	us-gaap	Equity Securities Fv Ni Gain Loss EquitySecuritiesFvNiGainLoss	49407000	USD
CY2019Q1	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	29351000	USD
CY2019Q2	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	1228000	USD
CY2019Q3	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	5556000	USD
CY2019Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	73895000	USD
CY2019Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	58165000	USD
CY2019Q4	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	185117000	USD
CY2019Q1	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	27600000	USD
CY2019Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	15200000	USD
CY2019Q4	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	39100000	USD
CY2019Q1	us-gaap	Profit Loss ProfitLoss	81702000	USD
CY2019Q2	us-gaap	Profit Loss ProfitLoss	57195000	USD
CY2019Q3	us-gaap	Profit Loss ProfitLoss	42965000	USD
CY2019Q4	us-gaap	Profit Loss ProfitLoss	146017000	USD
CY2019Q1	ghc	Income Loss Attributableto Redeemable Noncontrolling Interestand Nonredeemable Noncontrolling Interest IncomeLossAttributabletoRedeemableNoncontrollingInterestandNonredeemableNoncontrollingInterest	-46000	USD
CY2019Q2	ghc	Income Loss Attributableto Redeemable Noncontrolling Interestand Nonredeemable Noncontrolling Interest IncomeLossAttributabletoRedeemableNoncontrollingInterestandNonredeemableNoncontrollingInterest	114000	USD
CY2019Q3	ghc	Income Loss Attributableto Redeemable Noncontrolling Interestand Nonredeemable Noncontrolling Interest IncomeLossAttributabletoRedeemableNoncontrollingInterestandNonredeemableNoncontrollingInterest	-180000	USD
CY2019Q4	ghc	Income Loss Attributableto Redeemable Noncontrolling Interestand Nonredeemable Noncontrolling Interest IncomeLossAttributabletoRedeemableNoncontrollingInterestandNonredeemableNoncontrollingInterest	136000	USD
CY2019Q1	us-gaap	Net Income Loss NetIncomeLoss	81748000	USD
CY2019Q2	us-gaap	Net Income Loss NetIncomeLoss	57081000	USD
CY2019Q3	us-gaap	Net Income Loss NetIncomeLoss	43145000	USD
CY2019Q4	us-gaap	Net Income Loss NetIncomeLoss	145881000	USD
CY2019Q1	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	90038000	USD
CY2019Q2	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	44986000	USD
CY2019Q3	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	25059000	USD
CY2019Q4	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	267238000	USD
CY2019Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	15.38
CY2019Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	10.74
CY2019Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	8.12
CY2019Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	27.45
CY2019Q1	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	5284000	shares
CY2019Q2	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	5285000	shares
CY2019Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	5285000	shares
CY2018Q2	us-gaap	Revenues Revenues	672677000	USD
CY2018Q1	ghc	Operating Expense OperatingExpense	365151000	USD
CY2019Q4	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	5284000	shares
CY2019Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	15.26
CY2019Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	10.65
CY2019Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	8.05
CY2019Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	27.25
CY2019Q1	ghc	Weighted Average Number Of Potentially Dilutive Shares Outstanding WeightedAverageNumberOfPotentiallyDilutiveSharesOutstanding	5326000	shares
CY2019Q2	ghc	Weighted Average Number Of Potentially Dilutive Shares Outstanding WeightedAverageNumberOfPotentiallyDilutiveSharesOutstanding	5329000	shares
CY2019Q3	ghc	Weighted Average Number Of Potentially Dilutive Shares Outstanding WeightedAverageNumberOfPotentiallyDilutiveSharesOutstanding	5329000	shares
CY2019Q4	ghc	Weighted Average Number Of Potentially Dilutive Shares Outstanding WeightedAverageNumberOfPotentiallyDilutiveSharesOutstanding	5324000	shares
CY2018Q1	us-gaap	Revenues Revenues	659436000	USD
CY2018Q3	us-gaap	Revenues Revenues	674766000	USD
CY2018Q4	us-gaap	Revenues Revenues	689087000	USD
CY2018Q2	ghc	Operating Expense OperatingExpense	440655000	USD
CY2018Q3	ghc	Operating Expense OperatingExpense	448920000	USD
CY2018Q4	ghc	Operating Expense OperatingExpense	432706000	USD
CY2018Q1	ghc	Selling Generaland Administrative Expenses SellingGeneralandAdministrativeExpenses	225045000	USD
CY2018Q2	ghc	Selling Generaland Administrative Expenses SellingGeneralandAdministrativeExpenses	141378000	USD
CY2018Q3	ghc	Selling Generaland Administrative Expenses SellingGeneralandAdministrativeExpenses	131081000	USD
CY2018Q4	ghc	Selling Generaland Administrative Expenses SellingGeneralandAdministrativeExpenses	152624000	USD
CY2018Q1	us-gaap	Depreciation Depreciation	14642000	USD
CY2018Q2	us-gaap	Depreciation Depreciation	13619000	USD
CY2018Q3	us-gaap	Depreciation Depreciation	13648000	USD
CY2018Q4	us-gaap	Depreciation Depreciation	14813000	USD
CY2018Q1	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	10384000	USD
CY2018Q2	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	11399000	USD
CY2018Q3	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	12269000	USD
CY2018Q4	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	13362000	USD
CY2018Q1	us-gaap	Asset Impairment Charges AssetImpairmentCharges	0	USD
CY2018Q2	us-gaap	Asset Impairment Charges AssetImpairmentCharges	0	USD
CY2018Q3	us-gaap	Asset Impairment Charges AssetImpairmentCharges	8109000	USD
CY2018Q4	us-gaap	Asset Impairment Charges AssetImpairmentCharges	0	USD
CY2018Q1	us-gaap	Costs And Expenses CostsAndExpenses	615222000	USD
CY2018Q2	us-gaap	Costs And Expenses CostsAndExpenses	607051000	USD
CY2018Q3	us-gaap	Costs And Expenses CostsAndExpenses	614027000	USD
CY2018Q4	us-gaap	Costs And Expenses CostsAndExpenses	613505000	USD
CY2018Q1	us-gaap	Operating Income Loss OperatingIncomeLoss	44214000	USD
CY2018Q2	us-gaap	Operating Income Loss OperatingIncomeLoss	65626000	USD
CY2018Q3	us-gaap	Operating Income Loss OperatingIncomeLoss	60739000	USD
CY2018Q4	us-gaap	Operating Income Loss OperatingIncomeLoss	75582000	USD
CY2018Q1	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	2579000	USD
CY2018Q2	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	931000	USD
CY2018Q3	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	9537000	USD
CY2018Q4	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	1426000	USD
CY2018Q1	us-gaap	Investment Income Interest InvestmentIncomeInterest	1372000	USD
CY2018Q2	us-gaap	Investment Income Interest InvestmentIncomeInterest	1901000	USD
CY2018Q3	us-gaap	Investment Income Interest InvestmentIncomeInterest	611000	USD
CY2018Q4	us-gaap	Investment Income Interest InvestmentIncomeInterest	1469000	USD
CY2018Q1	us-gaap	Interest Expense InterestExpense	8071000	USD
CY2018Q2	us-gaap	Interest Expense InterestExpense	17165000	USD
CY2018Q3	us-gaap	Interest Expense InterestExpense	6135000	USD
CY2018Q4	us-gaap	Interest Expense InterestExpense	6531000	USD
CY2018Q1	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	0	USD
CY2018Q2	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	-11378000	USD
CY2018Q3	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	0	USD
CY2018Q4	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	0	USD
CY2018Q1	us-gaap	Net Periodic Defined Benefits Expense Reversal Of Expense Excluding Service Cost Component NetPeriodicDefinedBenefitsExpenseReversalOfExpenseExcludingServiceCostComponent	-21386000	USD
CY2018Q2	us-gaap	Net Periodic Defined Benefits Expense Reversal Of Expense Excluding Service Cost Component NetPeriodicDefinedBenefitsExpenseReversalOfExpenseExcludingServiceCostComponent	-23041000	USD
CY2018Q3	us-gaap	Net Periodic Defined Benefits Expense Reversal Of Expense Excluding Service Cost Component NetPeriodicDefinedBenefitsExpenseReversalOfExpenseExcludingServiceCostComponent	-22214000	USD
CY2018Q4	us-gaap	Net Periodic Defined Benefits Expense Reversal Of Expense Excluding Service Cost Component NetPeriodicDefinedBenefitsExpenseReversalOfExpenseExcludingServiceCostComponent	-53900000	USD
CY2018Q1	us-gaap	Equity Securities Fv Ni Gain Loss EquitySecuritiesFvNiGainLoss	-14102000	USD
CY2018Q2	us-gaap	Equity Securities Fv Ni Gain Loss EquitySecuritiesFvNiGainLoss	-2554000	USD
CY2018Q3	us-gaap	Equity Securities Fv Ni Gain Loss EquitySecuritiesFvNiGainLoss	44962000	USD
CY2018Q4	us-gaap	Equity Securities Fv Ni Gain Loss EquitySecuritiesFvNiGainLoss	-44149000	USD
CY2018Q1	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	9187000	USD
CY2018Q2	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	2333000	USD
CY2018Q3	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	3142000	USD
CY2018Q4	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	-12559000	USD
CY2018Q1	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	56565000	USD
CY2018Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	62735000	USD
CY2018Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	135070000	USD
CY2018Q4	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	69138000	USD
CY2018Q1	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	13600000	USD
CY2018Q2	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	16100000	USD
CY2018Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	10000000	USD
CY2018Q4	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	12400000	USD
CY2018Q1	us-gaap	Profit Loss ProfitLoss	42965000	USD
CY2018Q2	us-gaap	Profit Loss ProfitLoss	46635000	USD
CY2018Q3	us-gaap	Profit Loss ProfitLoss	125070000	USD
CY2018Q4	us-gaap	Profit Loss ProfitLoss	56738000	USD
CY2018Q1	ghc	Income Loss Attributableto Redeemable Noncontrolling Interestand Nonredeemable Noncontrolling Interest IncomeLossAttributabletoRedeemableNoncontrollingInterestandNonredeemableNoncontrollingInterest	74000	USD
CY2018Q2	ghc	Income Loss Attributableto Redeemable Noncontrolling Interestand Nonredeemable Noncontrolling Interest IncomeLossAttributabletoRedeemableNoncontrollingInterestandNonredeemableNoncontrollingInterest	69000	USD
CY2018Q3	ghc	Income Loss Attributableto Redeemable Noncontrolling Interestand Nonredeemable Noncontrolling Interest IncomeLossAttributabletoRedeemableNoncontrollingInterestandNonredeemableNoncontrollingInterest	6000	USD
CY2018Q4	ghc	Income Loss Attributableto Redeemable Noncontrolling Interestand Nonredeemable Noncontrolling Interest IncomeLossAttributabletoRedeemableNoncontrollingInterestandNonredeemableNoncontrollingInterest	53000	USD
CY2018Q1	us-gaap	Net Income Loss NetIncomeLoss	42891000	USD
CY2018Q2	us-gaap	Net Income Loss NetIncomeLoss	46566000	USD
CY2018Q3	us-gaap	Net Income Loss NetIncomeLoss	125064000	USD
CY2018Q4	us-gaap	Net Income Loss NetIncomeLoss	56685000	USD
CY2018Q1	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	53703000	USD
CY2018Q2	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	13345000	USD
CY2018Q3	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	119862000	USD
CY2018Q4	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	-52541000	USD
CY2018Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	7.84
CY2018Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	8.69
CY2018Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	23.43
CY2018Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	10.69
CY2018Q1	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	5436000	shares
CY2018Q2	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	5325000	shares
CY2018Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	5302000	shares
CY2018Q4	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	5270000	shares
CY2018Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	7.78
CY2018Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	8.63
CY2018Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	23.28
CY2018Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	10.61
CY2018Q1	ghc	Weighted Average Number Of Potentially Dilutive Shares Outstanding WeightedAverageNumberOfPotentiallyDilutiveSharesOutstanding	5473000	shares
CY2018Q2	ghc	Weighted Average Number Of Potentially Dilutive Shares Outstanding WeightedAverageNumberOfPotentiallyDilutiveSharesOutstanding	5362000	shares
CY2018Q3	ghc	Weighted Average Number Of Potentially Dilutive Shares Outstanding WeightedAverageNumberOfPotentiallyDilutiveSharesOutstanding	5337000	shares
CY2018Q4	ghc	Weighted Average Number Of Potentially Dilutive Shares Outstanding WeightedAverageNumberOfPotentiallyDilutiveSharesOutstanding	5309000	shares
CY2019Q1	ghc	Earnings Per Share Diluted Reductionto Operating Expensesin Associationwith Spectrum Repack Agreement EarningsPerShareDilutedReductiontoOperatingExpensesinAssociationwithSpectrumRepackAgreement	0.26
CY2019Q2	ghc	Earnings Per Share Diluted Reductionto Operating Expensesin Associationwith Spectrum Repack Agreement EarningsPerShareDilutedReductiontoOperatingExpensesinAssociationwithSpectrumRepackAgreement	1.13
CY2019Q3	ghc	Earnings Per Share Diluted Reductionto Operating Expensesin Associationwith Spectrum Repack Agreement EarningsPerShareDilutedReductiontoOperatingExpensesinAssociationwithSpectrumRepackAgreement	0.16
CY2019Q4	ghc	Earnings Per Share Diluted Reductionto Operating Expensesin Associationwith Spectrum Repack Agreement EarningsPerShareDilutedReductiontoOperatingExpensesinAssociationwithSpectrumRepackAgreement	0.15
CY2019Q4	ghc	Earnings Per Share Diluted Settlementgainrelatedtopensionannuitypurchase EarningsPerShareDilutedSettlementgainrelatedtopensionannuitypurchase	12.50
CY2019Q1	ghc	Earnings Per Share Diluted Losses On Marketable Equity Securities EarningsPerShareDilutedLossesOnMarketableEquitySecurities	3.37
CY2019Q2	ghc	Earnings Per Share Diluted Losses On Marketable Equity Securities EarningsPerShareDilutedLossesOnMarketableEquitySecurities	1.09
CY2019Q3	ghc	Earnings Per Share Diluted Losses On Marketable Equity Securities EarningsPerShareDilutedLossesOnMarketableEquitySecurities	2.44
CY2019Q4	ghc	Earnings Per Share Diluted Losses On Marketable Equity Securities EarningsPerShareDilutedLossesOnMarketableEquitySecurities	6.92
CY2019Q1	ghc	Earningsper Share Diluted Write Upsof Cost Method Investments EarningsperShareDilutedWriteUpsofCostMethodInvestments	0.22
CY2019Q3	ghc	Earningsper Share Diluted Write Upsof Cost Method Investments EarningsperShareDilutedWriteUpsofCostMethodInvestments	0.51
CY2019Q1	ghc	Earningsper Share Diluted Gainon Saleof Gimlet Media EarningsperShareDilutedGainonSaleofGimletMedia	4.06
CY2019Q1	ghc	Earnings Per Share Diluted Foreign Currency Transaction Gain Loss Unrealized EarningsPerShareDilutedForeignCurrencyTransactionGainLossUnrealized	0.07
CY2019Q2	ghc	Earnings Per Share Diluted Foreign Currency Transaction Gain Loss Unrealized EarningsPerShareDilutedForeignCurrencyTransactionGainLossUnrealized	0.02
CY2018Q4	ghc	Earnings Per Share Diluted Settlement Gain Related To Bulk Lump Sum Pension Offering And Curtailment Gain EarningsPerShareDilutedSettlementGainRelatedToBulkLumpSumPensionOfferingAndCurtailmentGain	4.11
CY2019Q3	ghc	Earnings Per Share Diluted Foreign Currency Transaction Gain Loss Unrealized EarningsPerShareDilutedForeignCurrencyTransactionGainLossUnrealized	0.09
CY2019Q4	ghc	Earnings Per Share Diluted Foreign Currency Transaction Gain Loss Unrealized EarningsPerShareDilutedForeignCurrencyTransactionGainLossUnrealized	-0.33
CY2019Q1	ghc	Earnings Per Share Diluted Effective Income Tax Rate Reconciliation Sharebased Compensation Excess Tax Benefit EarningsPerShareDilutedEffectiveIncomeTaxRateReconciliationSharebasedCompensationExcessTaxBenefit	0.32
CY2018Q1	ghc	Earnings Per Share Diluted Reductionto Operating Expensesin Associationwith Spectrum Repack Agreement EarningsPerShareDilutedReductiontoOperatingExpensesinAssociationwithSpectrumRepackAgreement	0.04
CY2018Q2	ghc	Earnings Per Share Diluted Reductionto Operating Expensesin Associationwith Spectrum Repack Agreement EarningsPerShareDilutedReductiontoOperatingExpensesinAssociationwithSpectrumRepackAgreement	0.11
CY2018Q3	ghc	Earnings Per Share Diluted Reductionto Operating Expensesin Associationwith Spectrum Repack Agreement EarningsPerShareDilutedReductiontoOperatingExpensesinAssociationwithSpectrumRepackAgreement	0.14
CY2018Q4	ghc	Earnings Per Share Diluted Reductionto Operating Expensesin Associationwith Spectrum Repack Agreement EarningsPerShareDilutedReductiontoOperatingExpensesinAssociationwithSpectrumRepackAgreement	0.26
CY2018Q2	ghc	Earnings Per Share Diluted Debt Extinguishment Costs EarningsPerShareDilutedDebtExtinguishmentCosts	-1.60
CY2018Q1	ghc	Earnings Per Share Diluted Losses On Marketable Equity Securities EarningsPerShareDilutedLossesOnMarketableEquitySecurities	-1.94
CY2018Q2	ghc	Earnings Per Share Diluted Losses On Marketable Equity Securities EarningsPerShareDilutedLossesOnMarketableEquitySecurities	-0.36
CY2018Q3	ghc	Earnings Per Share Diluted Losses On Marketable Equity Securities EarningsPerShareDilutedLossesOnMarketableEquitySecurities	6.26
CY2018Q4	ghc	Earnings Per Share Diluted Losses On Marketable Equity Securities EarningsPerShareDilutedLossesOnMarketableEquitySecurities	-6.28
CY2018Q1	ghc	Earnings Per Share Diluted Nonoperating Gain From Sales Writeups And Impairments Of Investments And Related To Sales Of Businesses Including Loss On Guarantor Obligations EarningsPerShareDilutedNonoperatingGainFromSalesWriteupsAndImpairmentsOfInvestmentsAndRelatedToSalesOfBusinessesIncludingLossOnGuarantorObligations	0.65
CY2018Q2	ghc	Earnings Per Share Diluted Nonoperating Gain From Sales Writeups And Impairments Of Investments And Related To Sales Of Businesses Including Loss On Guarantor Obligations EarningsPerShareDilutedNonoperatingGainFromSalesWriteupsAndImpairmentsOfInvestmentsAndRelatedToSalesOfBusinessesIncludingLossOnGuarantorObligations	0.34
CY2018Q3	ghc	Earnings Per Share Diluted Nonoperating Gain From Sales Writeups And Impairments Of Investments And Related To Sales Of Businesses Including Loss On Guarantor Obligations EarningsPerShareDilutedNonoperatingGainFromSalesWriteupsAndImpairmentsOfInvestmentsAndRelatedToSalesOfBusinessesIncludingLossOnGuarantorObligations	1.48
CY2018Q4	ghc	Earnings Per Share Diluted Nonoperating Gain From Sales Writeups And Impairments Of Investments And Related To Sales Of Businesses Including Loss On Guarantor Obligations EarningsPerShareDilutedNonoperatingGainFromSalesWriteupsAndImpairmentsOfInvestmentsAndRelatedToSalesOfBusinessesIncludingLossOnGuarantorObligations	-1.43
CY2018Q1	ghc	Earnings Per Share Diluted Foreign Currency Transaction Gain Loss Unrealized EarningsPerShareDilutedForeignCurrencyTransactionGainLossUnrealized	0.02
CY2018Q2	ghc	Earnings Per Share Diluted Foreign Currency Transaction Gain Loss Unrealized EarningsPerShareDilutedForeignCurrencyTransactionGainLossUnrealized	-0.32
CY2018Q3	ghc	Earnings Per Share Diluted Foreign Currency Transaction Gain Loss Unrealized EarningsPerShareDilutedForeignCurrencyTransactionGainLossUnrealized	-0.02
CY2018Q4	ghc	Earnings Per Share Diluted Foreign Currency Transaction Gain Loss Unrealized EarningsPerShareDilutedForeignCurrencyTransactionGainLossUnrealized	-0.23
CY2018Q3	ghc	Earnings Per Share Diluted Nonrecurring Discrete Deferred State Tax Benefit Related To The Release Of Valuation Allowances EarningsPerShareDilutedNonrecurringDiscreteDeferredStateTaxBenefitRelatedToTheReleaseOfValuationAllowances	3.31
CY2018Q1	ghc	Earnings Per Share Diluted Effective Income Tax Rate Reconciliation Sharebased Compensation Excess Tax Benefit EarningsPerShareDilutedEffectiveIncomeTaxRateReconciliationSharebasedCompensationExcessTaxBenefit	0.33

Files In Submission

Name	View Source	Status
0000104889-20-000007-index-headers.html	Edgar Link	pending
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0000104889-20-000007.txt	Edgar Link	pending
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$GHC
Graham Holdings Co Stock $ghc

2019 Q4 Form 10-K Financial Statement

#000010488920000007 Filed on February 26, 2020

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$GHC Graham Holdings Co Stock $ghc

2019 Q4 Form 10-K Financial Statement

#000010488920000007 Filed on February 26, 2020

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$GHC
Graham Holdings Co Stock $ghc