XML 91 R76.htm IDEA: XBRL DOCUMENT
v3.22.2.2

Financial Derivatives and Hedging Activities - Narrative (Detail) |  |  | 9 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | ---
Sep. 06, 2022 USD ($) | Jun. 15, 2022 USD ($) | Sep. 30, 2022 USD ($) | Sep. 30, 2021 USD ($) | Sep. 30, 2022 EUR (€) | Jun. 15, 2022 EUR (€) | Mar. 03, 2022
Derivative [Line Items] |  |  |  |  |  |  |
Pre-tax gain (loss) from changes in currency exchange rates |  |  | $ 27,500,000 | $ 13,800,000 |  |  |
Term Loans |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |
Line of credit facility, maximum borrowing capacity | € |  |  |  |  | € 220,000,000 |  |
Floating-to-fixed Interest Rate Swap Agreement |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |
Derivative notional amount | € |  |  |  |  |  | € 180,000,000 |
Derivative fixed interest rate (as a percent) |  |  |  |  |  | 0.0395% |
Loans variable rate of interest | € |  |  |  |  |  | € 180,000,000 |
Deferred gain on derivative |  | $ 400,000 |  |  |  |  |
Designated as Hedging | Currency Swap |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |
Derivative notional amount | $ 150,000,000 |  |  |  |  |  |
Derivative fixed interest rate (as a percent) |  |  |  |  |  |  | 3.06%
Derivative, interest rate swap (as a percent) |  |  |  |  |  |  | 4.75%
Proceeds from termination of cross-currency swap | $ 15,200,000 |  |  |  |  |  |
Minimum |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |
Long-term debt percentage bearing fixed Interest rate (as a percent) |  |  |  |  |  | 0.00% |
Minimum | Foreign Exchange Contract | Unrealized gain (loss) on derivatives |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |
Accumulated other comprehensive income realization period (in months) |  |  | 12 months |  |  |  |
Minimum | Cash Flow Hedges | Designated as Hedging |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |
Maturities of foreign currency derivative contracts (in months) |  |  | 1 month |  |  |  |
Maximum | Foreign Exchange Contract | Unrealized gain (loss) on derivatives |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |
Accumulated other comprehensive income realization period (in months) |  |  | 18 months |  |  |  |
Maximum | Cash Flow Hedges | Designated as Hedging |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |
Maturities of foreign currency derivative contracts (in months) |  |  | 18 months |  |  |  |

X
- Definition Period over which deferred gains or losses are expected to be reclassified out of accumulated other comprehensive income. + References No definition available. + Details
Name: | glt_AccumulatedOtherComprehensiveIncomeRealizationPeriod
Namespace Prefix: | glt_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Maturities of foreign currency derivative contracts. + References No definition available. + Details
Name: | glt_MaturitiesOfForeignCurrencyDerivativeContracts
Namespace Prefix: | glt_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Proceeds From Termination Of Hedging Instrument + References No definition available. + Details
Name: | glt_ProceedsFromTerminationOfHedgingInstrument
Namespace Prefix: | glt_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Fixed interest rate related to the interest rate derivative. + References No definition available. + Details
Name: | us-gaap_DerivativeFixedInterestRate
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Amount of increase in the fair value of derivatives recognized in the income statement. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4A -Subparagraph (b)(1) -URI https://asc.fasb.org/extlink&oid=125515794&loc=SL5618551-113959 + Details
Name: | us-gaap_DerivativeGainOnDerivative
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
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_DerivativeLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Nominal or face amount used to calculate payment on derivative. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1B -URI https://asc.fasb.org/extlink&oid=125515794&loc=SL5580258-113959 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (d) -URI https://asc.fasb.org/extlink&oid=125515794&loc=SL5579245-113959 + Details
Name: | us-gaap_DerivativeNotionalAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | instant

X
- Definition Fixed interest rate that will be received or paid upon exercise of the interest rate swaption contract. + References No definition available. + Details
Name: | us-gaap_DerivativeSwaptionInterestRate
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Amount before tax of foreign currency transaction realized and unrealized gain (loss) recognized in the income statement. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 830 -SubTopic 20 -Section 45 -Paragraph 1 -URI https://asc.fasb.org/extlink&oid=125521441&loc=d3e30690-110894 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 830 -SubTopic 20 -Section 35 -Paragraph 1 -URI https://asc.fasb.org/extlink&oid=123602790&loc=d3e30226-110892 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 830 -SubTopic 10 -Section 45 -Paragraph 17 -URI https://asc.fasb.org/extlink&oid=126980362&loc=d3e28228-110885 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 830 -SubTopic 20 -Section 50 -Paragraph 1 -URI https://asc.fasb.org/extlink&oid=124440516&loc=d3e30840-110895 + Details
Name: | us-gaap_ForeignCurrencyTransactionGainLossBeforeTax
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(b),22(b)) -URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
Name: | us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of loan with variable or adjustable rate of interest. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 45 -Paragraph 2 -URI https://asc.fasb.org/extlink&oid=124259787&loc=d3e4428-111522 + Details
Name: | us-gaap_LoansReceivableWithVariableRatesOfInterest1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a set, unchanging rate. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
Name: | us-gaap_LongTermDebtPercentageBearingFixedInterestRate
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | instant

X
- Details
Name: | us-gaap_DebtInstrumentAxis=glt_TermLoansMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=glt_FloatingToFixedInterestRateSwapAgreementMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_HedgingDesignationAxis=us-gaap_DesignatedAsHedgingInstrumentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=us-gaap_CurrencySwapMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=us-gaap_ForeignExchangeContractMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementEquityComponentsAxis=us-gaap_AccumulatedGainLossNetCashFlowHedgeParentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis=us-gaap_CashFlowHedgingMember
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: |