Line of Credit Facility, Additional Borrowing Capacity.

No definition available.

Name:	trex_LineOfCreditFacilityAdditionalBorrowingCapacity
Namespace Prefix:	trex_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Number of business days with in which lender may raise objections to amendment.

+ References

No definition available.

+ Details

Name:	trex_NumberOfBusinessDaysWithinWhichLenderMayRaiseObjectionsToAmendment
Namespace Prefix:	trex_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- 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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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Description of reference rate used for variable rate of debt instrument.

+ References

No definition available.

+ Details

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

- Definition

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

+ References

Reference 1: 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

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-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

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtWeightedAverageInterestRate
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

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

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16)(a)(2))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479440/944-210-S99-1

Reference 3: 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//1943274/2147479853/942-210-S99-1

+ Details

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

- Definition

Date the credit facility terminates, in YYYY-MM-DD format.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(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:dateItemType
Balance Type:	na
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/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

Name:	us-gaap_LineOfCreditFacilityLineItems
Namespace Prefix:	us-gaap_
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

+ Details

Name:	us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
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

+ Details

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

- Definition

The carrying value as of the balance sheet date of the current portion of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the 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(19))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-SubTopic 210
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(13))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1

+ Details

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

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
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Balance Type:
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- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_RevolvingCreditFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	trex_AgreementAxis=trex_FifthAmendmentAndRestatedAgreementMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	trex_CreditFacilityOneAxis=us-gaap_LetterOfCreditMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	trex_CreditFacilityOneAxis=trex_SwinglineLetterOfCreditMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
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Period Type:

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
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Balance Type:
Period Type:

- Details

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Debt - Additional Information (Detail) - USD ($)	6 Months Ended
Debt - Additional Information (Detail) - USD ($)	Jun. 30, 2023	Dec. 31, 2022	Dec. 22, 2022	May 26, 2022	May 18, 2022	May 26, 2020
Line of Credit Facility [Line Items]
Remaining available borrowing capacity	$ 344,000,000
Termination date of the Credit Agreement	Nov. 05, 2024
Outstanding borrowing capacity	$ 206,000,000	$ 222,000,000
Revolver Loans Portion Effective January 1 through June 30 [Member] \| Fourth Amended And Restated Credit Agreement [Member]
Line of Credit Facility [Line Items]
Revolving loans in a collective maximum principal amount	250,000,000
Revolver Loans Portion Effective July 1 through December 31 [Member] \| Fourth Amended And Restated Credit Agreement [Member]
Line of Credit Facility [Line Items]
Revolving loans in a collective maximum principal amount	$ 200,000,000
Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Revolving loans in a collective maximum principal amount				$ 100,000,000		$ 100,000,000
Debt, Weighted Average Interest Rate	6.15%
Revolving Credit Facility [Member] \| Fifth Amendment And Restated Agreement [Member]
Line of Credit Facility [Line Items]
Revolving loans in a collective maximum principal amount					$ 400,000,000
Termination date of the Credit Agreement	May 18, 2027
Number Of Business Days Within Which Lender May Raise Objections To Amendment	10 days
Revolving Credit Facility [Member] \| Fifth Amendment And Restated Agreement [Member] \| Letter of Credit [Member]
Line of Credit Facility [Line Items]
Revolving loans in a collective maximum principal amount					60,000,000
Revolving Credit Facility [Member] \| Fifth Amendment And Restated Agreement [Member] \| Swingline Letter Of Credit [Member]
Line of Credit Facility [Line Items]
Revolving loans in a collective maximum principal amount					$ 20,000,000
Revolving Credit Facility [Member] \| Base Rate [Member] \| Fifth Amendment And Restated Agreement [Member]
Line of Credit Facility [Line Items]
Interest rate	0.50%
Debt instrument, description of variable rate basis	the Federal Funds Rate plus 0.50%
Revolving Credit Facility [Member] \| Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate [Member] \| Fifth Amendment And Restated Agreement [Member]
Line of Credit Facility [Line Items]
Interest rate	1.00%
Debt instrument, description of variable rate basis	the Term SOFR plus 1.0%
Revolving B Loan [Member]
Line of Credit Facility [Line Items]
Long-Term Line of Credit	$ 150,000,000
Revolving B Loan [Member] \| Maximum [Member]
Line of Credit Facility [Line Items]
Debt instrument, Interest rate, Stated percentage	2.15%
Revolving B Loan [Member] \| Minimum [Member]
Line of Credit Facility [Line Items]
Debt instrument, Interest rate, Stated percentage	1.20%
Revolving B Loan [Member] \| Fifth Amendment And Restated Agreement [Member] \| Letter of Credit [Member]
Line of Credit Facility [Line Items]
Revolving loans in a collective maximum principal amount			$ 60,000,000
Revolving B Loan [Member] \| Fifth Amendment And Restated Agreement [Member] \| Swingline Letter Of Credit [Member]
Line of Credit Facility [Line Items]
Revolving loans in a collective maximum principal amount			$ 20,000,000
Revolving B Loan [Member] \| Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate [Member] \| Maximum [Member]
Line of Credit Facility [Line Items]
Interest rate	1.15%
Revolving B Loan [Member] \| Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate [Member] \| Minimum [Member]
Line of Credit Facility [Line Items]
Interest rate	0.20%