Annual Net Costs Mismatch Translation Exposure - Real vs US Dollar

No definition available.

Name:	tg_AnnualNetCostsMismatchTranslationExposureRealvsUSDollar
Namespace Prefix:	tg_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Commitment Under Cash Flow Hedges, Mass

+ References

No definition available.

+ Details

Name:	tg_CommitmentUnderCashFlowHedgesMass
Namespace Prefix:	tg_
Data Type:	dtr-types1:weightItemType
Balance Type:	na
Period Type:	instant

- Definition

The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480870/815-30-50-1

+ Details

Name:	us-gaap_CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonths
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- 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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480237/815-40-50-5

+ Details

Name:	us-gaap_DerivativeLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480434/815-10-50-1B

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1A
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480434/815-10-50-1A

+ Details

Name:	us-gaap_DerivativeNotionalAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	instant

- Details

Name:	us-gaap_DerivativeInstrumentRiskAxis=tg_AluminumFuturesContractsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DerivativeInstrumentRiskAxis=tg_TerphaneLtdaMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	tg_CashFlowHedgeMaturityDateAxis=tg_Oct2018Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Derivative Financial Instruments (Narrative) (Details) R$ in Thousands, $ in Thousands, lbs in Millions	3 Months Ended
	Mar. 31, 2023 USD ($) lbs	Mar. 31, 2023 BRL (R$)	Mar. 31, 2023 BRL (R$) lbs	Dec. 31, 2022 USD ($) lbs
Derivative [Line Items]
Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months	$ (900)
Aluminum Futures Contracts
Derivative [Line Items]
Derivative, Notional Amount	$ 27,800			$ 30,700
Commitment Under Cash Flow Hedges, Mass \| lbs	18.7		18.7	20.3
Terphane Ltda [Member]
Derivative [Line Items]
Derivative, Notional Amount	$ 25,674		R$ 147,245
Terphane Ltda [Member] \| Oct-2018 [Member]
Derivative [Line Items]
Annual Net Costs Mismatch Translation Exposure - Real vs US Dollar \| R$		R$ 177,000