XML 67 R45.htm IDEA: XBRL DOCUMENT
v3.22.4

Business And Summary Of Significant Accounting Policies (Narrative) (Details 1) | 12 Months Ended
--- | ---
Dec. 31, 2022
Minimum [Member] |
Revenue from External Customer [Line Items] |
Delivery Term1 | 1 year
Maximum [Member] |
Revenue from External Customer [Line Items] |
Term Of Contract | 5 years

X
- Definition Revenue From Contract With Customer, Delivery Term + References No definition available. + Details
Name: | gti_RevenueFromContractWithCustomerDeliveryTerm
Namespace Prefix: | gti_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Revenue From Contract With Customer, Term Of Contract + References No definition available. + Details
Name: | gti_RevenueFromContractWithCustomerTermOfContract
Namespace Prefix: | gti_
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_EntityWideInformationRevenueFromExternalCustomerLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

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: |