$EAF
GRAFTECH INTERNATIONAL LTD Stock $eaf

$eaf Overview Financials Valuation SEC Filings Company Website

2020 Form 10-K Financial Statement

#000093114821000035 Filed on February 23, 2021

Income Statement

Concept	2020	2019 Q4	2019
Revenue	$1.224B	$414.6M	$1.791B
YoY Change	-31.63%	-22.18%	-5.54%
Cost Of Revenue	$563.9M	$179.3M	$750.4M
YoY Change	-24.86%	-16.37%	6.33%
Gross Profit	$660.5M	$235.3M	$1.040B
YoY Change	-36.52%	-26.11%	-12.59%
Gross Profit Margin	53.95%	56.75%	58.1%
Selling, General & Admin	$67.91M	$17.30M	$63.67M
YoY Change	6.66%	10.31%	2.65%
% of Gross Profit	10.28%	7.35%	6.12%
Research & Development	$3.975M	$700.0K	$2.684M
YoY Change	48.1%	16.47%	26.07%
% of Gross Profit	0.6%	0.3%	0.26%
Depreciation & Amortization	$51.50M	$15.40M	$49.70M
YoY Change	3.62%	-17.65%	-7.1%
% of Gross Profit	7.8%	6.54%	4.78%
Operating Expenses	$71.89M	$18.10M	$66.36M
YoY Change	8.33%	11.15%	3.42%
Operating Profit	$588.6M	$217.2M	$974.0M
YoY Change	-39.57%	-28.11%	-13.5%
Interest Expense	$98.07M	-$27.10M	$127.3M
YoY Change	-22.98%	-20.53%	-5.72%
% of Operating Profit	16.66%	-12.48%	13.07%
Other Income/Expense, Net	-$3.330M	-$4.600M	-$5.203M
YoY Change	-36.0%	455.56%	54.81%
Pretax Income	$510.0M	$182.2M	$842.8M
YoY Change	-39.49%	-24.9%	-6.65%
Income Tax	$75.67M	$7.300M	$98.23M
% Of Pretax Income	14.84%	4.01%	11.65%
Net Earnings	$434.4M	$174.9M	$744.6M
YoY Change	-41.66%	-23.83%	-12.83%
Net Earnings / Revenue	35.48%	42.19%	41.58%
Basic Earnings Per Share	$1.62		$2.58
Diluted Earnings Per Share	$1.62	$613.7K	$2.58
COMMON SHARES
Basic Shares Outstanding	267.9M shares	289.5M shares	289.1M shares
Diluted Shares Outstanding	267.9M shares		289.1M shares

Balance Sheet

Concept	2020	2019 Q4	2019
SHORT-TERM ASSETS
Cash & Short-Term Investments	$145.4M	$80.90M	$80.90M
YoY Change	79.73%	62.12%	62.12%
Cash & Equivalents	$145.4M	$80.94M	$80.90M
Short-Term Investments
Other Short-Term Assets	$12.60M	$4.332M	$14.30M
YoY Change	-11.89%	-7.81%	-7.14%
Inventory	$277.8M	$313.6M	$326.4M
Prepaid Expenses
Receivables	$182.6M	$247.1M	$247.1M
Other Receivables	$10.70M	$0.00	$13.80M
Total Short-Term Assets	$629.2M	$682.6M	$682.6M
YoY Change	-7.82%	6.98%	6.97%
LONG-TERM ASSETS
Property, Plant & Equipment	$513.4M	$513.0M	$521.0M
YoY Change	-1.46%	-0.13%	1.42%
Goodwill		$171.1M
YoY Change		0.0%
Intangibles
YoY Change
Long-Term Investments
YoY Change
Other Assets	$46.60M	$104.2M	$67.60M
YoY Change	-31.07%	-6.02%	-21.94%
Total Long-Term Assets	$803.5M	$843.6M	$843.6M
YoY Change	-4.75%	-2.75%	-2.74%
TOTAL ASSETS
Total Short-Term Assets	$629.2M	$682.6M	$682.6M
Total Long-Term Assets	$803.5M	$843.6M	$843.6M
Total Assets	$1.433B	$1.526B	$1.526B
YoY Change	-6.13%	1.37%	1.37%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$71.00M	$78.70M	$78.70M
YoY Change	-9.78%	-10.67%	-10.67%
Accrued Expenses	$92.20M	$113.5M	$99.90M
YoY Change	-7.71%	-14.47%	-18.58%
Deferred Revenue
YoY Change
Short-Term Debt	$0.00	$141.0K	$0.00
YoY Change		-99.87%
Long-Term Debt Due	$100.0K	$141.0K	$100.0K
YoY Change	0.0%	-99.87%	-99.91%
Total Short-Term Liabilities	$198.1M	$220.2M	$220.2M
YoY Change	-10.04%	-32.68%	-32.68%
LONG-TERM LIABILITIES
Long-Term Debt	$1.420B	$1.813B	$1.813B
YoY Change	-21.66%	-11.59%	-11.59%
Other Long-Term Liabilities	$100.6M	$72.56M	$134.6M
YoY Change	-25.26%	0.06%	-15.35%
Total Long-Term Liabilities	$1.521B	$1.885B	$1.947B
YoY Change	-21.91%	-11.19%	-11.86%
TOTAL LIABILITIES
Total Short-Term Liabilities	$198.1M	$220.2M	$220.2M
Total Long-Term Liabilities	$1.521B	$1.885B	$1.947B
Total Liabilities	$1.762B	$2.105B	$2.217B
YoY Change	-20.53%	-14.06%	-14.14%
SHAREHOLDERS EQUITY
Retained Earnings		-$1.452B
YoY Change		-23.33%
Common Stock		$2.705M
YoY Change		-6.88%
Preferred Stock
YoY Change
Treasury Stock (at cost)
YoY Change
Treasury Stock Shares
Shareholders Equity	-$329.4M	-$691.1M	-$691.1M
YoY Change
Total Liabilities & Shareholders Equity	$1.433B	$1.526B	$1.526B
YoY Change	-6.13%	1.37%	1.37%

Cashflow Statement

Concept	2020	2019 Q4	2019
OPERATING ACTIVITIES
Net Income	$434.4M	$174.9M	$744.6M
YoY Change	-41.66%	-23.83%	-12.83%
Depreciation, Depletion And Amortization	$51.50M	$15.40M	$49.70M
YoY Change	3.62%	-17.65%	-7.1%
Cash From Operating Activities	$563.6M	$220.5M	$805.3M
YoY Change	-30.01%	-1.74%	-3.74%
INVESTING ACTIVITIES
Capital Expenditures	$36.08M	-$20.00M	$64.10M
YoY Change	-43.72%	-2.91%	-6.04%
Acquisitions
YoY Change
Other Investing Activities	$400.0K	$100.0K	$200.0K
YoY Change	100.0%		-77.78%
Cash From Investing Activities	-$35.70M	-$19.90M	-$63.88M
YoY Change	-44.12%	-2.93%	-5.07%
FINANCING ACTIVITIES
Cash Dividend Paid	$8.603M		$20.61M
YoY Change	-58.26%		-62.94%
Common Stock Issuance & Retirement, Net	$30.10M		$10.90M
YoY Change	176.15%
Debt Paid & Issued, Net			$350.1M
YoY Change			521.12%
Cash From Financing Activities	-$463.7M	-501.1M	-$709.6M
YoY Change	-34.66%	95.51%	-2.93%
NET CHANGE
Cash From Operating Activities	$563.6M	220.5M	$805.3M
Cash From Investing Activities	-$35.70M	-19.90M	-$63.88M
Cash From Financing Activities	-$463.7M	-501.1M	-$709.6M
Net Change In Cash	$64.27M	-300.5M	$31.80M
YoY Change	102.09%	473.47%	-16.89%
FREE CASH FLOW
Cash From Operating Activities	$563.6M	$220.5M	$805.3M
Capital Expenditures	$36.08M	-$20.00M	$64.10M
Free Cash Flow	$527.6M	$240.5M	$741.2M
YoY Change	-28.82%	-1.84%	-3.54%

Facts In Submission

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CY2020	dei	Entity File Number EntityFileNumber	1-13888
CY2020	dei	Entity Registrant Name EntityRegistrantName	GRAFTECH INTERNATIONAL LTD.
CY2020	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	DE
CY2020	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	27-2496053
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CY2020	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	267930644	shares
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	289074601	shares
CY2018	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	297753770	shares
CY2020	us-gaap	Net Income Loss NetIncomeLoss	434374000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	744602000	USD
	us-gaap	Net Income Loss NetIncomeLoss	854219000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Foreign Currency Translation Adjustment Tax OtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentTax	-162000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Foreign Currency Translation Adjustment Tax OtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentTax	-67000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Foreign Currency Translation Adjustment Tax OtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentTax	-288000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	6568000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	-6371000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	-18391000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Derivatives Qualifying As Hedges Tax OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesTax	5399000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Derivatives Qualifying As Hedges Tax OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesTax	-1546000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Derivatives Qualifying As Hedges Tax OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesTax	802000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Derivatives Qualifying As Hedges Net Of Tax OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax	-18848000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Derivatives Qualifying As Hedges Net Of Tax OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax	4810000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Derivatives Qualifying As Hedges Net Of Tax OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax	-7698000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-12280000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-1561000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-26089000	USD
CY2020	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	422094000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	743041000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	828130000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	434374000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	744602000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	854219000	USD
CY2020	us-gaap	Depreciation And Amortization DepreciationAndAmortization	62963000	USD
CY2019	us-gaap	Depreciation And Amortization DepreciationAndAmortization	61819000	USD
CY2018	us-gaap	Depreciation And Amortization DepreciationAndAmortization	66413000	USD
CY2020	us-gaap	Related Party Transaction Amounts Of Transaction RelatedPartyTransactionAmountsOfTransaction	-21090000	USD
CY2019	us-gaap	Related Party Transaction Amounts Of Transaction RelatedPartyTransactionAmountsOfTransaction	3393000	USD
CY2018	us-gaap	Related Party Transaction Amounts Of Transaction RelatedPartyTransactionAmountsOfTransaction	86478000	USD
CY2020	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	20241000	USD
CY2019	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	17503000	USD
CY2018	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-37078000	USD
CY2020	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	-8329000	USD
CY2019	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	0	USD
CY2018	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	-23827000	USD
CY2020	us-gaap	Paid In Kind Interest PaidInKindInterest	6192000	USD
CY2019	us-gaap	Paid In Kind Interest PaidInKindInterest	6344000	USD
CY2018	us-gaap	Paid In Kind Interest PaidInKindInterest	5320000	USD
CY2020	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-10526000	USD
CY2019	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-21831000	USD
CY2018	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-15761000	USD
CY2020	us-gaap	Increase Decrease In Operating Capital IncreaseDecreaseInOperatingCapital	-86438000	USD
CY2019	us-gaap	Increase Decrease In Operating Capital IncreaseDecreaseInOperatingCapital	47687000	USD
CY2018	us-gaap	Increase Decrease In Operating Capital IncreaseDecreaseInOperatingCapital	177754000	USD
CY2020	gti	Repayments Of Related Party Payable RepaymentsOfRelatedPartyPayable	27857000	USD
CY2019	gti	Repayments Of Related Party Payable RepaymentsOfRelatedPartyPayable	0	USD
CY2018	gti	Repayments Of Related Party Payable RepaymentsOfRelatedPartyPayable	0	USD
CY2020	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	16470000	USD
CY2019	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	2489000	USD
CY2018	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	583000	USD
CY2020	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	563646000	USD
CY2019	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	805316000	USD
CY2018	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	836603000	USD
CY2020	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	36075000	USD
CY2019	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	64103000	USD
CY2018	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	68221000	USD
CY2020	us-gaap	Proceeds From Sale Of Productive Assets ProceedsFromSaleOfProductiveAssets	379000	USD
CY2019	us-gaap	Proceeds From Sale Of Productive Assets ProceedsFromSaleOfProductiveAssets	219000	USD
CY2018	us-gaap	Proceeds From Sale Of Productive Assets ProceedsFromSaleOfProductiveAssets	926000	USD
CY2020	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-35696000	USD
CY2019	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-63884000	USD
CY2018	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-67295000	USD
CY2020	us-gaap	Repayments Of Other Short Term Debt RepaymentsOfOtherShortTermDebt	146000	USD
CY2019	us-gaap	Repayments Of Other Short Term Debt RepaymentsOfOtherShortTermDebt	0	USD
CY2018	us-gaap	Repayments Of Other Short Term Debt RepaymentsOfOtherShortTermDebt	12607000	USD
CY2020	us-gaap	Repayments Of Lines Of Credit RepaymentsOfLinesOfCredit	0	USD
CY2019	us-gaap	Repayments Of Lines Of Credit RepaymentsOfLinesOfCredit	0	USD
CY2018	us-gaap	Repayments Of Lines Of Credit RepaymentsOfLinesOfCredit	45692000	USD
CY2020	us-gaap	Payments Of Financing Costs PaymentsOfFinancingCosts	6278000	USD
CY2019	us-gaap	Payments Of Financing Costs PaymentsOfFinancingCosts	0	USD
CY2018	us-gaap	Payments Of Financing Costs PaymentsOfFinancingCosts	27326000	USD
CY2020	us-gaap	Proceeds From Issuance Of Secured Debt ProceedsFromIssuanceOfSecuredDebt	500000000	USD
CY2019	us-gaap	Proceeds From Issuance Of Secured Debt ProceedsFromIssuanceOfSecuredDebt	0	USD
CY2018	us-gaap	Proceeds From Issuance Of Secured Debt ProceedsFromIssuanceOfSecuredDebt	2235000000	USD
CY2020	us-gaap	Early Repayment Of Subordinated Debt EarlyRepaymentOfSubordinatedDebt	0	USD
CY2019	us-gaap	Early Repayment Of Subordinated Debt EarlyRepaymentOfSubordinatedDebt	0	USD
CY2018	us-gaap	Early Repayment Of Subordinated Debt EarlyRepaymentOfSubordinatedDebt	304782000	USD
CY2020	gti	Related Party Stock Repurchase RelatedPartyStockRepurchase	0	USD
CY2019	gti	Related Party Stock Repurchase RelatedPartyStockRepurchase	250000000	USD
CY2018	gti	Related Party Stock Repurchase RelatedPartyStockRepurchase	225000000	USD
CY2020	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	30099000	USD
CY2019	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	10868000	USD
CY2018	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	0	USD
CY2020	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	71000	USD
CY2019	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	0	USD
CY2018	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	0	USD
CY2020	us-gaap	Repayments Of Secured Debt RepaymentsOfSecuredDebt	896214000	USD
CY2019	us-gaap	Repayments Of Secured Debt RepaymentsOfSecuredDebt	350140000	USD
CY2018	us-gaap	Repayments Of Secured Debt RepaymentsOfSecuredDebt	56372000	USD
CY2020	us-gaap	Payments Of Dividends PaymentsOfDividends	8603000	USD
CY2019	us-gaap	Payments Of Dividends PaymentsOfDividends	20613000	USD
CY2018	us-gaap	Payments Of Dividends PaymentsOfDividends	55616000	USD
CY2020	gti	Payment Of Dividends Related Party PaymentOfDividendsRelatedParty	22272000	USD
CY2019	gti	Payment Of Dividends Related Party PaymentOfDividendsRelatedParty	78010000	USD
CY2018	gti	Payment Of Dividends Related Party PaymentOfDividendsRelatedParty	1488649000	USD
CY2020	us-gaap	Repayments Of Related Party Debt RepaymentsOfRelatedPartyDebt	0	USD
CY2019	us-gaap	Repayments Of Related Party Debt RepaymentsOfRelatedPartyDebt	0	USD
CY2018	us-gaap	Repayments Of Related Party Debt RepaymentsOfRelatedPartyDebt	750000000	USD
CY2020	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-463683000	USD
CY2019	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-709631000	USD
CY2018	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-731044000	USD
CY2020	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	64267000	USD
CY2019	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	31801000	USD
CY2018	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	38264000	USD
CY2020	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	240000	USD
CY2019	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	-746000	USD
CY2018	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	-1749000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	80935000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	49880000	USD
CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	13365000	USD
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	145442000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	80935000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	49880000	USD
CY2020	us-gaap	Interest Paid Net InterestPaidNet	86962000	USD
CY2019	us-gaap	Interest Paid Net InterestPaidNet	121075000	USD
CY2018	us-gaap	Interest Paid Net InterestPaidNet	108006000	USD
CY2020	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	73971000	USD
CY2019	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	99278000	USD
CY2018	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	21444000	USD
CY2020	us-gaap	Stock Issued1 StockIssued1	0	USD
CY2019	us-gaap	Stock Issued1 StockIssued1	0	USD
CY2018	us-gaap	Stock Issued1 StockIssued1	750000000	USD
CY2020	us-gaap	Increase Decrease In Accounts And Notes Receivable IncreaseDecreaseInAccountsAndNotesReceivable	-63557000	USD
CY2019	us-gaap	Increase Decrease In Accounts And Notes Receivable IncreaseDecreaseInAccountsAndNotesReceivable	404000	USD
CY2018	us-gaap	Increase Decrease In Accounts And Notes Receivable IncreaseDecreaseInAccountsAndNotesReceivable	139180000	USD
CY2020	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	-44633000	USD
CY2019	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	21549000	USD
CY2018	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	126355000	USD
CY2020	us-gaap	Increase Decrease In Prepaid Deferred Expense And Other Assets IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets	-3028000	USD
CY2019	us-gaap	Increase Decrease In Prepaid Deferred Expense And Other Assets IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets	-3929000	USD
CY2018	us-gaap	Increase Decrease In Prepaid Deferred Expense And Other Assets IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets	-7116000	USD
CY2020	us-gaap	Increase Decrease In Accrued Income Taxes Payable IncreaseDecreaseInAccruedIncomeTaxesPayable	-12420000	USD
CY2019	us-gaap	Increase Decrease In Accrued Income Taxes Payable IncreaseDecreaseInAccruedIncomeTaxesPayable	-18174000	USD
CY2018	us-gaap	Increase Decrease In Accrued Income Taxes Payable IncreaseDecreaseInAccruedIncomeTaxesPayable	67054000	USD
CY2020	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	-12790000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	-18391000	USD
CY2019	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	10868000	USD
CY2019	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	2146000	USD
CY2019	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	-11551000	USD
CY2018	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	15724000	USD
CY2020	us-gaap	Increase Decrease In Interest Payable Net IncreaseDecreaseInInterestPayableNet	430000	USD
CY2019	us-gaap	Increase Decrease In Interest Payable Net IncreaseDecreaseInInterestPayableNet	62000	USD
CY2018	us-gaap	Increase Decrease In Interest Payable Net IncreaseDecreaseInInterestPayableNet	-2113000	USD
CY2020	us-gaap	Increase Decrease In Operating Capital IncreaseDecreaseInOperatingCapital	-86438000	USD
CY2019	us-gaap	Increase Decrease In Operating Capital IncreaseDecreaseInOperatingCapital	47687000	USD
CY2018	us-gaap	Increase Decrease In Operating Capital IncreaseDecreaseInOperatingCapital	177754000	USD
CY2018Q2	us-gaap	Stock Issued1 StockIssued1	750000000	USD
CY2017Q4	us-gaap	Stockholders Equity StockholdersEquity	613215000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	854219000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax	715000	USD
CY2018	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-6866000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationTax	87000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci On Derivatives Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesTax	-832000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Foreign Currency Translation Adjustment Tax OtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentTax	-288000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-26089000	USD
CY2018	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	225000000	USD
CY2018	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	1151000	USD
CY2018	gti	Payment Of Dividends Related Party PaymentOfDividendsRelatedParty	1488649000	USD
CY2018	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.9345
CY2018	us-gaap	Payments Of Dividends PaymentsOfDividends	55616000	USD
CY2018	us-gaap	Repayment Of Notes Receivable From Related Parties RepaymentOfNotesReceivableFromRelatedParties	750000000	USD
CY2018Q4	us-gaap	Stockholders Equity StockholdersEquity	-1076769000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	744602000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax	-3418000	USD
CY2019	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	11830000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationTax	1872000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci On Derivatives Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesTax	-7020000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Foreign Currency Translation Adjustment Tax OtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentTax	-67000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	-6371000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-1561000	USD
CY2019	gti	Payment Of Dividends Related Party PaymentOfDividendsRelatedParty	78010000	USD
CY2019	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.34
CY2019	us-gaap	Payments Of Dividends PaymentsOfDividends	20613000	USD
CY2019Q4	us-gaap	Stockholders Equity StockholdersEquity	-691073000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	434374000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax	4250000	USD
CY2020	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-15594000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationTax	879000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci On Derivatives Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesTax	-3254000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Foreign Currency Translation Adjustment Tax OtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentTax	-162000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	6568000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-12280000	USD
CY2020	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	30099000	USD
CY2020	us-gaap	Stock Issued During Period Shares Employee Stock Ownership Plan StockIssuedDuringPeriodSharesEmployeeStockOwnershipPlan	42411	shares
CY2020	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	2665000	USD
CY2020	gti	Payment Of Dividends Related Party PaymentOfDividendsRelatedParty	22272000	USD
CY2020	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.115
CY2020	us-gaap	Payments Of Dividends PaymentsOfDividends	8603000	USD
CY2020	us-gaap	Adjustments Related To Tax Withholding For Share Based Compensation AdjustmentsRelatedToTaxWithholdingForShareBasedCompensation	71000	USD
CY2020Q4	us-gaap	Stockholders Equity StockholdersEquity	-329385000	USD
CY2020	us-gaap	Nature Of Operations NatureOfOperations	Discussion of Business and Structure
CY2020	us-gaap	Depreciation Depreciation	51500000	USD
CY2019	us-gaap	Depreciation Depreciation	49700000	USD
CY2018	us-gaap	Depreciation Depreciation	53500000	USD
CY2020Q4	gti	Capital Expenses Incurred But Not Yetpaid CapitalExpensesIncurredButNotYetpaid	8900000	USD
CY2019Q4	gti	Capital Expenses Incurred But Not Yetpaid CapitalExpensesIncurredButNotYetpaid	11500000	USD
CY2020Q4	us-gaap	Other Deferred Costs Gross OtherDeferredCostsGross	18100000	USD
CY2019Q4	us-gaap	Other Deferred Costs Gross OtherDeferredCostsGross	20200000	USD
CY2020	us-gaap	Amortization Of Deferred Charges AmortizationOfDeferredCharges	9200000	USD
CY2019	us-gaap	Amortization Of Deferred Charges AmortizationOfDeferredCharges	4100000	USD
CY2018	us-gaap	Amortization Of Deferred Charges AmortizationOfDeferredCharges	3500000	USD
CY2018Q2	gti	Related Party Tax Agreement Percent Of Savings RelatedPartyTaxAgreementPercentOfSavings	0.85
CY2020	us-gaap	Environmental Remediation Expense EnvironmentalRemediationExpense	11100000	USD
CY2019	us-gaap	Environmental Remediation Expense EnvironmentalRemediationExpense	11600000	USD
CY2018	us-gaap	Environmental Remediation Expense EnvironmentalRemediationExpense	12400000	USD
CY2019	us-gaap	Accrual For Environmental Loss Contingencies Charges To Expense For New Losses AccrualForEnvironmentalLossContingenciesChargesToExpenseForNewLosses	4900000	USD
CY2020	us-gaap	Accrual For Environmental Loss Contingencies Charges To Expense For New Losses AccrualForEnvironmentalLossContingenciesChargesToExpenseForNewLosses	4900000	USD
CY2020Q4	gti	Capitalized Maintenance Cost CapitalizedMaintenanceCost	10200000	USD
CY2019Q4	gti	Capitalized Maintenance Cost CapitalizedMaintenanceCost	800000	USD
CY2020	gti	Amortization Deferred Maintenance Cost AmortizationDeferredMaintenanceCost	6000000.0	USD
CY2019	gti	Amortization Deferred Maintenance Cost AmortizationDeferredMaintenanceCost	5100000	USD
CY2018	gti	Amortization Deferred Maintenance Cost AmortizationDeferredMaintenanceCost	3100000	USD
CY2020	us-gaap	Use Of Estimates UseOfEstimates	<div style="margin-top:9pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:700;line-height:120%">Use of Estimates</span></div><div style="margin-top:9pt;text-align:justify;text-indent:42.75pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">The preparation of financial statements in conformity with U.S. generally accepted accounting principles (“GAAP”) requires us to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent liabilities at the date of the Consolidated Financial Statements and the reported amounts of revenue and expenses. Significant estimates and assumptions are used for, but are not limited to inventory valuation, pension and other post-retirement benefits, allowance for doubtful accounts, contingent liabilities, accruals and valuation allowances, asset impairment, and environmental-related accruals. Actual results could differ from our estimates.</span></div>
CY2020	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	1224361000	USD
CY2019	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	1790793000	USD
CY2018	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	1895910000	USD
CY2020Q4	us-gaap	Contract With Customer Asset Gross ContractWithCustomerAssetGross	2700000	USD
CY2020Q4	us-gaap	Contract With Customer Asset Accumulated Allowance For Credit Loss Current ContractWithCustomerAssetAccumulatedAllowanceForCreditLossCurrent	1500000	USD
CY2019Q4	us-gaap	Contract With Customer Asset Accumulated Allowance For Credit Loss Noncurrent ContractWithCustomerAssetAccumulatedAllowanceForCreditLossNoncurrent	1200000	USD
CY2019Q4	us-gaap	Contract With Customer Asset Gross ContractWithCustomerAssetGross	0	USD
CY2020	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	2700000	USD
CY2019	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	2100000	USD
CY2018	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	1200000	USD
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Gross ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross	308875	shares
CY2020	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Grants In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice	3.11
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Gross ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross	229250	shares
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue	5.13
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Gross ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross	979790	shares
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue	6.08
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Volatility Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate	0.50
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Volatility Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate	0.50
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Volatility Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate	0.45
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Risk Free Interest Rate Minimum ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMinimum	0.0037
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Risk Free Interest Rate Maximum ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMaximum	0.0122
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Risk Free Interest Rate Minimum ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMinimum	0.0179
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Risk Free Interest Rate Maximum ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMaximum	0.0263
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Risk Free Interest Rate Minimum ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMinimum	0.0284
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Risk Free Interest Rate Maximum ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMaximum	0.0298
CY2020	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Fair Value Assumptions Expected Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1	P6Y6M
CY2019	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Fair Value Assumptions Expected Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1	P6Y6M
CY2018	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Fair Value Assumptions Expected Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1	P6Y6M
CY2020	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Outstanding Weighted Average Remaining Contractual Term2 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2	P7Y10M24D
CY2019	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Outstanding Weighted Average Remaining Contractual Term2 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2	P2Y10M24D
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue	500000	USD
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	1248935	shares
CY2020	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Outstanding Weighted Average Remaining Contractual Term2 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2	P7Y10M24D
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	13.66
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber	342574	shares
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice	15.38
CY2019Q4	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Nonvested Number Of Shares SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedNumberOfShares	931658	shares
CY2019Q4	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Nonvested Weighted Average Grant Date Fair Value SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedWeightedAverageGrantDateFairValue	15.06
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Gross ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross	308875	shares
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue	8.99
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Vested And Expected To Vest Exercisable Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableNumber	190212	shares
CY2020	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Vested Weighted Average Grant Date Fair Value SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedWeightedAverageGrantDateFairValue	15.13
CY2020	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Nonvested Options Forfeited Number Of Shares SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedOptionsForfeitedNumberOfShares	143960	shares
CY2020	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Nonvested Options Forfeited Weighted Average Grant Date Fair Value SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedOptionsForfeitedWeightedAverageGrantDateFairValue	14.82
CY2020Q4	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Nonvested Number Of Shares SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedNumberOfShares	906361	shares
CY2020Q4	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Nonvested Weighted Average Grant Date Fair Value SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedWeightedAverageGrantDateFairValue	13.01
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Vested And Expected To Vest Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingNumber	303583	shares
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber	342574	shares
CY2020Q4	us-gaap	Deferred Compensation Sharebased Arrangements Liability Current And Noncurrent DeferredCompensationSharebasedArrangementsLiabilityCurrentAndNoncurrent	8900000	USD
CY2019Q4	us-gaap	Deferred Compensation Sharebased Arrangements Liability Current And Noncurrent DeferredCompensationSharebasedArrangementsLiabilityCurrentAndNoncurrent	6900000	USD
CY2020	us-gaap	Interest Expense Debt Excluding Amortization InterestExpenseDebtExcludingAmortization	83555000	USD
CY2019	us-gaap	Interest Expense Debt Excluding Amortization InterestExpenseDebtExcludingAmortization	121010000	USD
CY2020	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	1224361000	USD
CY2019	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	1790793000	USD
CY2018	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	1895910000	USD
CY2020Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	506217000	USD
CY2019Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	513020000	USD
CY2020Q4	us-gaap	Long Term Debt LongTermDebt	1420131000	USD
CY2019Q4	us-gaap	Long Term Debt LongTermDebt	1812823000	USD
CY2020Q4	us-gaap	Long Term Debt Current LongTermDebtCurrent	131000	USD
CY2019Q4	us-gaap	Long Term Debt Current LongTermDebtCurrent	141000	USD
CY2020Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	1420000000	USD
CY2019Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	1812682000	USD
CY2018Q1	gti	Equity Interest Pledge EquityInterestPledge	0.65
CY2020Q4	us-gaap	Debt Instrument Repurchase Amount DebtInstrumentRepurchaseAmount	80000000	USD
CY2020Q4	us-gaap	Subordinated Borrowing Interest Rate SubordinatedBorrowingInterestRate	0.04625
CY2020Q4	us-gaap	Debt Instrument Redemption Price Percentage DebtInstrumentRedemptionPricePercentage	1
CY2020Q4	us-gaap	Subordinated Borrowing Interest Rate SubordinatedBorrowingInterestRate	0.04625
CY2020	us-gaap	Debt Instrument Redemption Price Percentage Of Principal Amount Redeemed DebtInstrumentRedemptionPricePercentageOfPrincipalAmountRedeemed	0.30
CY2018	us-gaap	Interest Expense Debt Excluding Amortization InterestExpenseDebtExcludingAmortization	100844000	USD
CY2020	us-gaap	Interest Expense Related Party InterestExpenseRelatedParty	0	USD
CY2019	us-gaap	Interest Expense Related Party InterestExpenseRelatedParty	0	USD
CY2018	us-gaap	Interest Expense Related Party InterestExpenseRelatedParty	5090000	USD
CY2020	us-gaap	Redemption Premium RedemptionPremium	0	USD
CY2019	us-gaap	Redemption Premium RedemptionPremium	0	USD
CY2018	us-gaap	Redemption Premium RedemptionPremium	4782000	USD
CY2020	gti	Accretion Expenseon Extinguished Debt AccretionExpenseonExtinguishedDebt	0	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	142300000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	69871000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	72429000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	142300000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	58446000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	83854000	USD
CY2020	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	11400000	USD
CY2019	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	12200000	USD
	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	12900000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Next Twelve Months FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths	10700000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Two FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo	10100000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Three FiniteLivedIntangibleAssetsAmortizationExpenseYearThree	9200000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Four FiniteLivedIntangibleAssetsAmortizationExpenseYearFour	8000000.0	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Five FiniteLivedIntangibleAssetsAmortizationExpenseYearFive	7300000	USD
CY2019	us-gaap	Accretion Expense AccretionExpense	2196000	USD
CY2019	gti	Accretion Expenseon Extinguished Debt AccretionExpenseonExtinguishedDebt	0	USD
CY2018	gti	Accretion Expenseon Extinguished Debt AccretionExpenseonExtinguishedDebt	19414000	USD
CY2020	us-gaap	Accretion Expense AccretionExpense	5340000	USD
CY2020Q4	us-gaap	Machinery And Equipment Gross MachineryAndEquipmentGross	621478000	USD
CY2019Q4	us-gaap	Machinery And Equipment Gross MachineryAndEquipmentGross	567715000	USD
CY2020Q4	us-gaap	Construction In Progress Gross ConstructionInProgressGross	33098000	USD
CY2019Q4	us-gaap	Construction In Progress Gross ConstructionInProgressGross	47370000	USD
CY2020Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	784902000	USD
CY2019Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	733417000	USD
CY2020Q4	us-gaap	Accrued Employee Benefits Current And Noncurrent AccruedEmployeeBenefitsCurrentAndNoncurrent	13159000	USD
CY2019Q4	us-gaap	Accrued Employee Benefits Current And Noncurrent AccruedEmployeeBenefitsCurrentAndNoncurrent	11801000	USD
CY2020Q4	us-gaap	Accrued Employee Benefits Current AccruedEmployeeBenefitsCurrent	7128000	USD
CY2019Q4	us-gaap	Accrued Employee Benefits Current AccruedEmployeeBenefitsCurrent	7416000	USD
CY2020	us-gaap	Other Comprehensive Income Foreign Currency Transaction And Translation Gain Loss Arising During Period Net Of Tax OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationGainLossArisingDuringPeriodNetOfTax	1200000	USD
CY2019	us-gaap	Other Comprehensive Income Foreign Currency Transaction And Translation Gain Loss Arising During Period Net Of Tax OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationGainLossArisingDuringPeriodNetOfTax	0	USD
CY2020	us-gaap	Cash Flow Hedge Gain Loss To Be Reclassified Within Twelve Months CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonths	7400000	USD
CY2019	us-gaap	Cash Flow Hedge Gain Loss To Be Reclassified Within Twelve Months CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonths	3500000	USD
CY2020Q4	us-gaap	Inventory Raw Materials And Supplies InventoryRawMaterialsAndSupplies	101098000	USD
CY2019Q4	us-gaap	Inventory Raw Materials And Supplies InventoryRawMaterialsAndSupplies	129879000	USD
CY2020Q4	us-gaap	Inventory Work In Process InventoryWorkInProcess	110331000	USD
CY2019Q4	us-gaap	Inventory Work In Process InventoryWorkInProcess	131435000	USD
CY2020Q4	us-gaap	Inventory Finished Goods InventoryFinishedGoods	54535000	USD
CY2019Q4	us-gaap	Inventory Finished Goods InventoryFinishedGoods	52334000	USD
CY2020Q4	us-gaap	Inventory Net InventoryNet	265964000	USD
CY2019Q4	us-gaap	Inventory Net InventoryNet	313648000	USD
CY2020Q4	us-gaap	Other Prepaid Expense Current OtherPrepaidExpenseCurrent	9242000	USD
CY2019Q4	us-gaap	Other Prepaid Expense Current OtherPrepaidExpenseCurrent	9986000	USD
CY2020Q4	us-gaap	Prepaid Taxes PrepaidTaxes	10666000	USD
CY2019Q4	us-gaap	Prepaid Taxes PrepaidTaxes	13890000	USD
CY2020Q4	us-gaap	Other Inventories Spare Parts OtherInventoriesSpareParts	11825000	USD
CY2019Q4	us-gaap	Other Inventories Spare Parts OtherInventoriesSpareParts	12738000	USD
CY2020Q4	us-gaap	Other Assets Current OtherAssetsCurrent	3381000	USD
CY2019Q4	us-gaap	Other Assets Current OtherAssetsCurrent	4332000	USD
CY2020Q4	us-gaap	Prepaid Expense And Other Assets Current PrepaidExpenseAndOtherAssetsCurrent	35114000	USD
CY2019Q4	us-gaap	Prepaid Expense And Other Assets Current PrepaidExpenseAndOtherAssetsCurrent	40946000	USD
CY2020Q4	us-gaap	Land Land	50285000	USD
CY2019Q4	us-gaap	Land Land	46548000	USD
CY2020Q4	us-gaap	Buildings And Improvements Gross BuildingsAndImprovementsGross	80041000	USD
CY2019Q4	us-gaap	Buildings And Improvements Gross BuildingsAndImprovementsGross	71784000	USD
CY2019Q4	us-gaap	Postemployment Benefits Liability Noncurrent PostemploymentBenefitsLiabilityNoncurrent	16528000	USD
CY2020Q4	us-gaap	Deferred Revenue DeferredRevenue	13056000	USD
CY2019Q4	us-gaap	Deferred Revenue DeferredRevenue	11776000	USD
CY2020Q4	us-gaap	Other Accrued Liabilities Current And Noncurrent OtherAccruedLiabilitiesCurrentAndNoncurrent	23158000	USD
CY2019Q4	us-gaap	Other Accrued Liabilities Current And Noncurrent OtherAccruedLiabilitiesCurrentAndNoncurrent	17342000	USD
CY2020Q4	us-gaap	Accrued Liabilities Current And Noncurrent AccruedLiabilitiesCurrentAndNoncurrent	56501000	USD
CY2019Q4	us-gaap	Accrued Liabilities Current And Noncurrent AccruedLiabilitiesCurrentAndNoncurrent	48335000	USD
CY2020Q4	us-gaap	Postemployment Benefits Liability Noncurrent PostemploymentBenefitsLiabilityNoncurrent	15669000	USD
CY2018	us-gaap	Accretion Expense AccretionExpense	1455000	USD
CY2020	us-gaap	Amortization Of Financing Costs AmortizationOfFinancingCosts	9179000	USD
CY2019	us-gaap	Amortization Of Financing Costs AmortizationOfFinancingCosts	4125000	USD
CY2018	us-gaap	Amortization Of Financing Costs AmortizationOfFinancingCosts	3476000	USD
CY2020	us-gaap	Interest Expense InterestExpense	98074000	USD
CY2019	us-gaap	Interest Expense InterestExpense	127331000	USD
CY2018	us-gaap	Interest Expense InterestExpense	135061000	USD
CY2020Q4	us-gaap	Subordinated Borrowing Interest Rate SubordinatedBorrowingInterestRate	0.04625
CY2020	us-gaap	Line Of Credit Facility Interest Rate During Period LineOfCreditFacilityInterestRateDuringPeriod	0.0450
CY2019	us-gaap	Line Of Credit Facility Interest Rate During Period LineOfCreditFacilityInterestRateDuringPeriod	0.0530
CY2018	us-gaap	Line Of Credit Facility Interest Rate During Period LineOfCreditFacilityInterestRateDuringPeriod	0.0602
CY2018	us-gaap	Redemption Premium RedemptionPremium	4800000	USD
CY2018	gti	Accretion Expenseon Extinguished Debt AccretionExpenseonExtinguishedDebt	19400000	USD
CY2019	gti	Accelerated Accretion AcceleratedAccretion	18700000	USD
CY2019	gti	Accelerated Amortizationof Debt Issuance Costs AcceleratedAmortizationofDebtIssuanceCosts	300000	USD
CY2020Q4	us-gaap	Debt Instrument Interest Rate Effective Percentage DebtInstrumentInterestRateEffectivePercentage	0.051
CY2019Q4	gti	Hedging Instruments Nonderivative Assets HedgingInstrumentsNonderivativeAssets	5500000	USD
CY2020Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	3195000	USD
CY2019Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	3598000	USD
CY2018	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	122000	USD
CY2020	us-gaap	Allowance For Doubtful Accounts Receivable Period Increase Decrease AllowanceForDoubtfulAccountsReceivablePeriodIncreaseDecrease	-715000	USD
CY2019	us-gaap	Allowance For Doubtful Accounts Receivable Period Increase Decrease AllowanceForDoubtfulAccountsReceivablePeriodIncreaseDecrease	-291000	USD
CY2018	us-gaap	Allowance For Doubtful Accounts Receivable Period Increase Decrease AllowanceForDoubtfulAccountsReceivablePeriodIncreaseDecrease	-90000	USD
CY2020Q4	us-gaap	Allowance For Doubtful Accounts Receivable AllowanceForDoubtfulAccountsReceivable	8243000	USD
CY2019Q4	us-gaap	Allowance For Doubtful Accounts Receivable AllowanceForDoubtfulAccountsReceivable	5474000	USD
CY2018Q4	us-gaap	Allowance For Doubtful Accounts Receivable AllowanceForDoubtfulAccountsReceivable	1129000	USD
CY2019Q1	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	7500000	USD
CY2019Q1	us-gaap	Operating Lease Liability OperatingLeaseLiability	7500000	USD
CY2020	us-gaap	Operating Lease Cost OperatingLeaseCost	6138000	USD
CY2019	us-gaap	Operating Lease Cost OperatingLeaseCost	4816000	USD
CY2020	us-gaap	Short Term Lease Cost ShortTermLeaseCost	159000	USD
CY2019Q4	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	4475000	USD
CY2019	us-gaap	Short Term Lease Cost ShortTermLeaseCost	14000	USD
CY2020	us-gaap	Variable Lease Cost VariableLeaseCost	429000	USD
CY2019	us-gaap	Variable Lease Cost VariableLeaseCost	227000	USD
CY2020	us-gaap	Lease Cost LeaseCost	6726000	USD
CY2019	us-gaap	Lease Cost LeaseCost	5057000	USD
CY2020	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	5262000	USD
CY2019	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	4995000	USD
CY2020	us-gaap	Operating Lease Payments OperatingLeasePayments	6177000	USD
CY2019	us-gaap	Operating Lease Payments OperatingLeasePayments	4724000	USD
CY2020Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	7164000	USD
CY2019Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	7994000	USD
CY2020Q4	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	4102000	USD
CY2020Q4	gti	Pension And Related Benefits PensionAndRelatedBenefits	37847000	USD
CY2019Q4	gti	Pension And Related Benefits PensionAndRelatedBenefits	37431000	USD
CY2020Q4	us-gaap	Other Long Term Debt Noncurrent OtherLongTermDebtNoncurrent	27962000	USD
CY2019Q4	us-gaap	Other Long Term Debt Noncurrent OtherLongTermDebtNoncurrent	18603000	USD
CY2020Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	81478000	USD
CY2019Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	72562000	USD
CY2019	us-gaap	Increase Decrease In Raw Materials Packaging Materials And Supplies Inventories IncreaseDecreaseInRawMaterialsPackagingMaterialsAndSuppliesInventories	25100000	USD
CY2019	gti	Increase Decrease In Work In Process Inventories IncreaseDecreaseInWorkInProcessInventories	5800000	USD
CY2019	gti	Increase Decrease In Finished Goods Inventories IncreaseDecreaseInFinishedGoodsInventories	19300000	USD
CY2019Q4	us-gaap	Allowance For Doubtful Accounts Receivable AllowanceForDoubtfulAccountsReceivable	5474000	USD
CY2018Q4	us-gaap	Allowance For Doubtful Accounts Receivable AllowanceForDoubtfulAccountsReceivable	1129000	USD
CY2017Q4	us-gaap	Allowance For Doubtful Accounts Receivable AllowanceForDoubtfulAccountsReceivable	1097000	USD
CY2020	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	1458000	USD
CY2019	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	4636000	USD
CY2020Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	7297000	USD
CY1991Q1	us-gaap	Defined Contribution Plan Maximum Annual Contributions Per Employee Percent DefinedContributionPlanMaximumAnnualContributionsPerEmployeePercent	0.06
CY2020Q4	us-gaap	Defined Benefit Plan Accumulated Benefit Obligation DefinedBenefitPlanAccumulatedBenefitObligation	176300000	USD
CY2020Q4	us-gaap	Defined Benefit Plan Assumptions Used Calculating Benefit Obligation Discount Rate DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate	0.0178
CY2019Q4	us-gaap	Defined Benefit Plan Assumptions Used Calculating Benefit Obligation Discount Rate DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate	0.0259
CY2020Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	7297000	USD
CY2019Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	8073000	USD
CY2020Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P2Y8M12D
CY2019Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P2Y3M18D
CY2020Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.0582
CY2019Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.0561
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Next Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	4124000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	1377000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	1024000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	872000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	449000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	7846000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	549000	USD
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CY2019Q4	us-gaap	Defined Benefit Plan Fair Value Of Plan Assets DefinedBenefitPlanFairValueOfPlanAssets	126812000	USD
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CY2019	us-gaap	Defined Benefit Plan Assumptions Used Calculating Net Periodic Benefit Cost Rate Of Compensation Increase DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostRateOfCompensationIncrease	0.0174
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CY2019	us-gaap	Pension And Other Postretirement Benefit Contributions PensionAndOtherPostretirementBenefitContributions	2100000	USD
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CY2018Q4	us-gaap	Product Warranty Accrual ProductWarrantyAccrual	1528000	USD
CY2019	us-gaap	Product Warranty Expense ProductWarrantyExpense	1033000	USD
CY2019	us-gaap	Product Warranty Accrual Payments ProductWarrantyAccrualPayments	726000	USD
CY2019Q4	us-gaap	Product Warranty Accrual ProductWarrantyAccrual	1835000	USD
CY2020	us-gaap	Product Warranty Expense ProductWarrantyExpense	1220000	USD
CY2020	us-gaap	Product Warranty Accrual Payments ProductWarrantyAccrualPayments	1058000	USD
CY2020Q4	us-gaap	Product Warranty Accrual ProductWarrantyAccrual	1997000	USD
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CY2019Q4	us-gaap	Due To Related Parties Current And Noncurrent DueToRelatedPartiesCurrentAndNoncurrent	89900000	USD
CY2019Q4	us-gaap	Due To Related Parties Current DueToRelatedPartiesCurrent	27900000	USD
CY2019Q4	us-gaap	Due To Related Parties Noncurrent DueToRelatedPartiesNoncurrent	62000000.0	USD
CY2020	us-gaap	Increase Decrease In Due To Related Parties IncreaseDecreaseInDueToRelatedParties	21100000	USD
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CY2020Q4	us-gaap	Due To Related Parties Current DueToRelatedPartiesCurrent	21800000	USD
CY2020Q4	us-gaap	Due To Related Parties Noncurrent DueToRelatedPartiesNoncurrent	19100000	USD
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CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	970840000	USD
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CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	902808000	USD
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CY2019	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	5690000	USD
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CY2020	us-gaap	Federal Income Tax Expense Benefit Continuing Operations FederalIncomeTaxExpenseBenefitContinuingOperations	20162000	USD
CY2019	us-gaap	Federal Income Tax Expense Benefit Continuing Operations FederalIncomeTaxExpenseBenefitContinuingOperations	22279000	USD
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CY2019	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	64134000	USD
CY2018	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	85252000	USD
CY2020	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	-7583000	USD
CY2019	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	11812000	USD
CY2018	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	15026000	USD
CY2020	us-gaap	Foreign Income Tax Expense Benefit Continuing Operations ForeignIncomeTaxExpenseBenefitContinuingOperations	55509000	USD
CY2019	us-gaap	Foreign Income Tax Expense Benefit Continuing Operations ForeignIncomeTaxExpenseBenefitContinuingOperations	75946000	USD
CY2018	us-gaap	Foreign Income Tax Expense Benefit Continuing Operations ForeignIncomeTaxExpenseBenefitContinuingOperations	100278000	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	75671000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	98225000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	48920000	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	75700000	USD
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	510000000.0	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	98200000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	842800000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	48900000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	902800000	USD
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CY2019	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	176994000	USD
CY2018	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	189590000	USD
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CY2020	us-gaap	Income Tax Reconciliation Tax Settlements IncomeTaxReconciliationTaxSettlements	-4429000	USD
CY2019	us-gaap	Income Tax Reconciliation Tax Settlements IncomeTaxReconciliationTaxSettlements	713000	USD
CY2018	us-gaap	Income Tax Reconciliation Tax Settlements IncomeTaxReconciliationTaxSettlements	18160000	USD
CY2020	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	-980000	USD
CY2019	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	-14548000	USD
CY2018	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	1529000	USD
CY2018	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	-93125000	USD
CY2020	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	3591000	USD
CY2019	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	4231000	USD
CY2020	us-gaap	Income Tax Reconciliation Repatriation Of Foreign Earnings IncomeTaxReconciliationRepatriationOfForeignEarnings	2113000	USD
CY2019	us-gaap	Income Tax Reconciliation Repatriation Of Foreign Earnings IncomeTaxReconciliationRepatriationOfForeignEarnings	2181000	USD
CY2018	us-gaap	Income Tax Reconciliation Repatriation Of Foreign Earnings IncomeTaxReconciliationRepatriationOfForeignEarnings	792000	USD
CY2020	us-gaap	Income Tax Reconciliation Tax Contingencies IncomeTaxReconciliationTaxContingencies	-78000	USD
CY2019	us-gaap	Income Tax Reconciliation Tax Contingencies IncomeTaxReconciliationTaxContingencies	-1293000	USD
CY2018	us-gaap	Income Tax Reconciliation Tax Contingencies IncomeTaxReconciliationTaxContingencies	-345000	USD
CY2020	us-gaap	Income Tax Reconciliation Foreign Income Tax Rate Differential IncomeTaxReconciliationForeignIncomeTaxRateDifferential	-38464000	USD
CY2019	us-gaap	Income Tax Reconciliation Foreign Income Tax Rate Differential IncomeTaxReconciliationForeignIncomeTaxRateDifferential	-76922000	USD
CY2018	us-gaap	Income Tax Reconciliation Foreign Income Tax Rate Differential IncomeTaxReconciliationForeignIncomeTaxRateDifferential	-95822000	USD
CY2020	us-gaap	Income Tax Reconciliation Tax Credits IncomeTaxReconciliationTaxCredits	37280000	USD
CY2019	us-gaap	Income Tax Reconciliation Tax Credits IncomeTaxReconciliationTaxCredits	56171000	USD
CY2018	us-gaap	Income Tax Reconciliation Tax Credits IncomeTaxReconciliationTaxCredits	65046000	USD
CY2020	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	-1450000	USD
CY2019	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	-2491000	USD
CY2018	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	-552000	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	75671000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	98225000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	48920000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Postretirement Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsPostretirementBenefits	18202000	USD
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CY2020Q4	us-gaap	Deferred Tax Assets Tax Credit Carryforwards DeferredTaxAssetsTaxCreditCarryforwards	37101000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Credit Carryforwards DeferredTaxAssetsTaxCreditCarryforwards	55103000	USD
CY2020Q4	gti	Deferred Tax Assets Deferred Expense Capitalized Research And Development Costs DeferredTaxAssetsDeferredExpenseCapitalizedResearchAndDevelopmentCosts	3897000	USD
CY2019Q4	gti	Deferred Tax Assets Deferred Expense Capitalized Research And Development Costs DeferredTaxAssetsDeferredExpenseCapitalizedResearchAndDevelopmentCosts	5566000	USD
CY2020Q4	gti	Deferred Tax Assets Environmental Reserves DeferredTaxAssetsEnvironmentalReserves	1111000	USD
CY2019Q4	gti	Deferred Tax Assets Environmental Reserves DeferredTaxAssetsEnvironmentalReserves	1110000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Inventory DeferredTaxAssetsInventory	7381000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Inventory DeferredTaxAssetsInventory	14863000	USD
CY2020Q4	gti	Deferred Tax Liabilities Inventory DeferredTaxLiabilitiesInventory	8573000	USD
CY2019Q4	gti	Deferred Tax Liabilities Inventory DeferredTaxLiabilitiesInventory	12778000	USD
CY2020Q4	gti	Deferred Tax Asset Option Amortization DeferredTaxAssetOptionAmortization	1031000	USD
CY2019Q4	gti	Deferred Tax Asset Option Amortization DeferredTaxAssetOptionAmortization	1080000	USD
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CY2020Q4	us-gaap	Deferred Tax Assets Derivative Instruments DeferredTaxAssetsDerivativeInstruments	3552000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Derivative Instruments DeferredTaxAssetsDerivativeInstruments	768000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	3646000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	1104000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	76017000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	98082000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	12773000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	13736000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	63244000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	84346000	USD
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CY2020Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	3254000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	2468000	USD
CY2020Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	73864000	USD
CY2019Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	78901000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	10620000	USD
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CY2019Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	84300000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	63200000	USD
CY2019Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	78900000	USD
CY2020Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	73900000	USD
CY2018Q4	us-gaap	Valuation Allowances And Reserves Balance ValuationAllowancesAndReservesBalance	58446000	USD
CY2019	us-gaap	Valuation Allowances And Reserves Deductions ValuationAllowancesAndReservesDeductions	14548000	USD
CY2019	us-gaap	Valuation Allowances And Reserves Adjustments ValuationAllowancesAndReservesAdjustments	-30138000	USD
CY2019	gti	Valuation Allowance Changesin Underlying Assets ValuationAllowanceChangesinUnderlyingAssets	-24000	USD
CY2019Q4	us-gaap	Valuation Allowances And Reserves Balance ValuationAllowancesAndReservesBalance	13736000	USD
CY2020	us-gaap	Valuation Allowances And Reserves Deductions ValuationAllowancesAndReservesDeductions	980000	USD
CY2020	us-gaap	Valuation Allowances And Reserves Adjustments ValuationAllowancesAndReservesAdjustments	17000	USD
CY2020Q4	us-gaap	Valuation Allowances And Reserves Balance ValuationAllowancesAndReservesBalance	12773000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Credit Carryforwards Foreign DeferredTaxAssetsTaxCreditCarryforwardsForeign	17900000	USD
CY2020Q4	us-gaap	Operating Loss Carryforwards OperatingLossCarryforwards	255700000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Deferred Income DeferredTaxAssetsDeferredIncome	15000000.0	USD
CY2020Q4	us-gaap	Unrecognized Tax Benefits That Would Impact Effective Tax Rate UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate	100000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards Foreign DeferredTaxAssetsOperatingLossCarryforwardsForeign	9100000	USD
CY2020Q4	us-gaap	Unrecognized Tax Benefits That Would Impact Effective Tax Rate UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate	100000	USD
CY2018Q4	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Accrued UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued	900000	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Accrued UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued	0	USD
CY2019	gti	Unrecognized Tax Benefits Increase Decrease Income Tax Penaltiesand Interest Accrued UnrecognizedTaxBenefitsIncreaseDecreaseIncomeTaxPenaltiesandInterestAccrued	900000	USD
CY2018Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	1990000	USD
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CY2019Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	184000	USD
CY2019	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	421000	USD
CY2019	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Foreign Currency Translation UnrecognizedTaxBenefitsDecreasesResultingFromForeignCurrencyTranslation	2000	USD
CY2020	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations	75000	USD
CY2020	us-gaap	Unrecognized Tax Benefits Increases Resulting From Foreign Currency Translation UnrecognizedTaxBenefitsIncreasesResultingFromForeignCurrencyTranslation	16000	USD
CY2020Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	125000	USD
CY2020Q4	us-gaap	Decrease In Unrecognized Tax Benefits Is Reasonably Possible DecreaseInUnrecognizedTaxBenefitsIsReasonablyPossible	100000	USD
CY2020Q4	us-gaap	Undistributed Earnings Of Foreign Subsidiaries UndistributedEarningsOfForeignSubsidiaries	1200000000	USD
CY2020Q4	gti	Undistributed Earningsof Foreign Subsidiaries Subjectedto One Time Transition Fee UndistributedEarningsofForeignSubsidiariesSubjectedtoOneTimeTransitionFee	1000000000.0	USD
CY2018Q2	us-gaap	Stock Issued During Period Shares Stock Splits StockIssuedDuringPeriodSharesStockSplits	3022259.23	shares
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CY2018Q2	gti	Default Event Threshold DefaultEventThreshold	1.75
CY2018Q2	us-gaap	Stock Issued During Period Shares New Issues StockIssuedDuringPeriodSharesNewIssues	35000000	shares
CY2018Q2	us-gaap	Sale Of Stock Price Per Share SaleOfStockPricePerShare	15
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	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.01
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	289057356	shares
CY2018	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	297748327	shares
CY2020	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	14161	shares
CY2019	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	17245	shares
CY2018	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	5443	shares
CY2020	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	267930644	shares
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	289074601	shares
CY2018	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	297753770	shares
CY2020Q4	gti	Participating Securities ParticipatingSecurities	73320	shares
CY2019Q4	gti	Participating Securities ParticipatingSecurities	32981	shares
CY2018Q4	gti	Participating Securities ParticipatingSecurities	5592	shares
CY2020	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	1667325	shares
CY2019	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	1082113	shares
CY2018	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	650432	shares

Files In Submission

Name	View Source	Status
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0000931148-21-000035-index.html	Edgar Link	pending
0000931148-21-000035.txt	Edgar Link	pending
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$EAF
GRAFTECH INTERNATIONAL LTD Stock $eaf

2020 Form 10-K Financial Statement

#000093114821000035 Filed on February 23, 2021

Income Statement

Balance Sheet

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Facts In Submission

Files In Submission

$EAF GRAFTECH INTERNATIONAL LTD Stock $eaf

2020 Form 10-K Financial Statement

#000093114821000035 Filed on February 23, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$EAF
GRAFTECH INTERNATIONAL LTD Stock $eaf