Debt Instrument, Basis Spread On Variable Rate, Floor

No definition available.

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- Definition

Debt Instrument, Borrowing Base Calculation, Amount Of Eligible Cash, Cap, Percentage Of Borrowing Base

+ References

No definition available.

+ Details

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- Definition

Debt Instrument, Borrowing Base Calculation, Property Plant And Equipment Component Threshold, Percentage Of Borrowing Base

+ References

No definition available.

+ Details

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- Definition

Debt Instrument, Borrowing Base Calculation, Property Plant And Equipment Component Threshold, Percentage Of Net Orderly Liquidation Value

+ References

No definition available.

+ Details

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- Definition

Debt Instrument, Covenant, Fixed Charge Coverage Ratio

+ References

No definition available.

+ Details

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- Definition

Line Of Credit, Cash Dominion Period, Monetary Availability Threshold

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line Of Credit, Cash Dominion Period, Percentage Threshold

+ References

No definition available.

+ Details

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- Definition

Line of Credit Facility, percent borrowing capacity

+ References

No definition available.

+ Details

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- Definition

Line of Credit Facility, Unused Capacity, Commitment Fee Percentage, Threshold

+ References

No definition available.

+ Details

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- Definition

Line Of Credit, Fixed Charge Coverage Ratio, Monetary Availability Threshold

+ References

No definition available.

+ Details

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Namespace Prefix:	tg_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line Of Credit, Fixed Charge Coverage Ratio, Percentage Threshold

+ References

No definition available.

+ Details

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- Definition

Line of Credit, Maximum Borrowing Capacity after ABL Adjustment Date

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line of Credit, Maximum Borrowing Capacity after Modification

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Minimum Availability after ABL Adjustment Date

+ References

No definition available.

+ Details

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Data Type:	dtr-types:percentItemType
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- Definition

Amount of assets pledged to secure a debt instrument.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477734/942-470-50-3

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22)(a)(1))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1B

+ Details

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- 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 470
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481544/470-10-50-6

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481544/470-10-50-6

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(f))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-1

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- 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
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22)(b))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(19)(b))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481544/470-10-50-6

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22)(b))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(19)(b))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

The carrying amount as of the balance sheet date for the aggregate of other miscellaneous borrowings owed by the reporting entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(13))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1

+ Details

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- Details

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DEBT (Details) ¥ in Millions, $ in Millions				3 Months Ended
DEBT (Details) ¥ in Millions, $ in Millions	May 06, 2025 USD ($)	May 05, 2025	Jun. 25, 2024 CNY (¥)	Mar. 31, 2025 USD ($) Rate	Mar. 31, 2025 CNY (¥) Rate	Dec. 27, 2023 USD ($)
Line of Credit Facility [Line Items]
Line of credit facility						$ 180.0
Maximum borrowing capacity after modification				$ 180.0
Maximum borrowing capacity after ABL adjustment				125.0
Remaining borrowing capacity				$ 50.9
Percentage of remaining borrowing capacity \| Rate				40.70%	40.70%
Minimum availability before ABL adjustment \| Rate				10.00%	10.00%
Minimum availability after ABL adjustment \| Rate				20.00%	20.00%
Cash Dominion Period availability \| Rate				12.50%	12.50%
Guangzhou Tredegar Loan
Line of Credit Facility [Line Items]
Basis spread on variable rate			0.45%
Borrowing \| ¥			¥ 9.5
Interest rate				2.90%	2.90%
Mortgage contract maximum value \| ¥					¥ 30.0
Revolving Credit Facility \| Amended ABL Facility \| Subsequent Event
Line of Credit Facility [Line Items]
Line of credit facility	$ 125.0
Commitment fee percentage threshold	50.00%
Property, plant, and equipment component threshold, percentage of net orderly liquidation value	60.00%
Property, plant, and equipment component threshold, percentage of borrowing base	30.00%
Amount of eligible cash, cap, percentage of borrowing base	15.00%
Fixed charge coverage ratio	1.00
Revolving Credit Facility \| Amended ABL Facility \| Federal Reserve Bank Of New York Rate
Line of Credit Facility [Line Items]
Basis spread on variable rate				0.05%
Revolving Credit Facility \| Amended ABL Facility \| Adjusted Term Secured Overnight Financing Rate (SOFR)
Line of Credit Facility [Line Items]
Basis spread on variable rate				1.00%
Revolving Credit Facility \| Amended ABL Facility \| Term Secured Overnight Financing Rate
Line of Credit Facility [Line Items]
Basis spread on variable rate				0.10%
Initial floor percentage				0.00%
Revolving Credit Facility \| Amended ABL Facility \| Base Rate \| Subsequent Event
Line of Credit Facility [Line Items]
Cash Dominion Period availability	0.125
Cash dominion period, monetary availability threshold	$ 12.6
Revolving Credit Facility \| Amended ABL Facility \| Fixed Charge Coverage Ratio \| Subsequent Event
Line of Credit Facility [Line Items]
Minimum availability before ABL adjustment	0.10
Fixed charge coverage ratio, monetary availability threshold	$ 10.0
Revolving Credit Facility \| Term Benchmark Loan And RFR Loan \| Base Rate \| Subsequent Event \| Minimum
Line of Credit Facility [Line Items]
Basis spread on variable rate	1.75%
Revolving Credit Facility \| Term Benchmark Loan And RFR Loan \| Base Rate \| Subsequent Event \| Maximum
Line of Credit Facility [Line Items]
Basis spread on variable rate	2.25%
Revolving Credit Facility \| ABR Loan \| Base Rate \| Subsequent Event \| Minimum
Line of Credit Facility [Line Items]
Basis spread on variable rate	0.75%
Revolving Credit Facility \| ABR Loan \| Base Rate \| Subsequent Event \| Maximum
Line of Credit Facility [Line Items]
Basis spread on variable rate	1.25%
Revolving Credit Facility \| Amended ABL Facility If Average Usage Is Greater Than Or Equal To 50% \| Subsequent Event
Line of Credit Facility [Line Items]
Commitment fee percentage	0.25%	0.40%
Revolving Credit Facility \| Amended ABL Facility If Average Usage Is Less Than 50% \| Subsequent Event
Line of Credit Facility [Line Items]
Commitment fee percentage	0.375%