XML 64 R54.htm IDEA: XBRL DOCUMENT
v3.19.2

Leases (Narrative) (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2019 | Jun. 30, 2019 | Dec. 31, 2018
Lessee, Lease, Description [Line Items] |  |  |
Lease Cost Net of Sublease Income | $ 29,804 | $ 59,331 |
Lessee, operating lease, lease not yet commenced, payments due | $ 25,900 | $ 25,900 |
Future minimum sublease payments due |  |  | $ 66,000
Minimum [Member] |  |  |
Lessee, Lease, Description [Line Items] |  |  |
Lessee, operating lease, renewal or termination option term |  | 1 year |
Lessee, operating lease, lease not yet commenced, term of contract | 2 years | 2 years |
Maximum [Member] |  |  |
Lessee, Lease, Description [Line Items] |  |  |
Lessee, operating lease, renewal or termination option term |  | 10 years |
Lessee, operating lease, lease not yet commenced, term of contract | 20 years | 20 years |
Sale of KHE Campuses business [Member] |  |  |
Lessee, Lease, Description [Line Items] |  |  |
Lease Cost Net of Sublease Income | $ 300 | $ 600 |

X
- Definition Amount of lease cost, net of sublease income, recognized by lessee for lease contract + References No definition available. + Details
Name: | ghc_LeaseCostNetofSubleaseIncome
Namespace Prefix: | ghc_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Payments due for operating lease arrangements which have not yet commenced as of the date of the balance sheet + References No definition available. + Details
Name: | ghc_LesseeOperatingLeaseLeaseNotyetCommencedPaymentsDue
Namespace Prefix: | ghc_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Term of lessee's option to renew or terminate an operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References No definition available. + Details
Name: | ghc_LesseeOperatingLeaseRenewalorTerminationOptionTerm
Namespace Prefix: | ghc_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_LesseeLeaseDescriptionLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Term of lessee's operating lease not yet commenced, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918673-209980 + Details
Name: | us-gaap_LesseeOperatingLeaseLeaseNotYetCommencedTermOfContract1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | instant

X
- Definition Contractually required future rental payments receivable on noncancelable subleasing arrangements. + References Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 20 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=77902758&loc=d3e41502-112717 + Details
Name: | us-gaap_OperatingLeasesFutureMinimumPaymentsDueFutureMinimumSubleaseRentals
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | srt_RangeAxis=srt_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ghc_TransactionAxis=ghc_SaleOfKHECampusesBusinessMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |