XML 177 R116.htm IDEA: XBRL DOCUMENT
v3.24.0.1

Income Taxes (Schedule Of Valuation Allowance Activity) (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Income Tax Disclosure [Abstract] |  |  |
Balance at beginning of year | $ 9,269 | $ 10,550 | $ 12,773
Credited to income | (268) | (1,259) | (2,208)
Translation adjustment | (45) | (22) | (15)
Balance at end of year | $ 8,956 | $ 9,269 | $ 10,550

X
- Definition Valuation Allowance, Changes in Underlying Assets + References No definition available. + Details
Name: | gti_ValuationAllowanceChangesinUnderlyingAssets
Namespace Prefix: | gti_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_IncomeTaxDisclosureAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of valuation and qualifying accounts and reserves. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 235 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 4 -Subparagraph (SX 210.12-09(Column B)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480678/235-10-S99-4 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 235 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 4 -Subparagraph (SX 210.12-09(Column E)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480678/235-10-S99-4 + Details
Name: | us-gaap_ValuationAllowancesAndReservesBalance
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of decrease in valuation and qualifying accounts and reserves. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 235 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 4 -Subparagraph (SX 210.12-09(Column D)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480678/235-10-S99-4 + Details
Name: | us-gaap_ValuationAllowancesAndReservesDeductions
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration