Average period for PE material purchases under short term supply contracts for which pricing is negotiated as needed.

No definition available.

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

- Definition

Land improvements term period.

+ References

No definition available.

+ Details

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

- Definition

Percentage change in the expected number of remaining claims to be settled with payment or the expected cost to settle claims used as a threshold for disclosure.

+ References

No definition available.

+ Details

Name:	trex_PercentSensitivityChangeInExpectedSurfaceFlakingClaims
Namespace Prefix:	trex_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Schedule of commitments and contingencies.

+ References

No definition available.

+ Details

Name:	trex_ScheduleOfCommitmentsAndContingenciesLineItems
Namespace Prefix:	trex_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Estimated change in the warranty reserve resulting from a 10% change in the expected number of remaining claims to be settled with payment or the expected cost to settle claims for disclosure purposes only.

+ References

No definition available.

+ Details

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

- Definition

The number of years the Company warrants that its products will be free from material defects in workmanship and materials.

+ References

No definition available.

+ Details

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

- Definition

Area of land held.

+ References

No definition available.

+ Details

Name:	us-gaap_AreaOfLand
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:areaItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount before accumulated deprecation and depletion of real estate held for productive use and additions or improvements to real estate held for productive use, examples include, but are not limited to, walkways, driveways, fences, and parking lots. Excludes land held for sale.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section 45
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=124098289&loc=d3e6812-107765

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(13))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

Name:	us-gaap_LandAndLandImprovements
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of purchase arrangement to be paid in fourth fiscal year following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

No definition available.

+ Details

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

- Definition

Amount of purchase arrangement to be paid in second fiscal year following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

No definition available.

+ Details

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

- Definition

Amount of purchase arrangement to be paid in third fiscal year following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

No definition available.

+ Details

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

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_ResidentialPortfolioSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
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Balance Type:
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- Details

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ValuationAllowancesAndReservesTypeAxis=trex_SurfaceFlakingWarrantyReserveMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_GuaranteeObligationsByNatureAxis=trex_ResidentialUseMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_GuaranteeObligationsByNatureAxis=trex_CommercialUseMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_ProductOrServiceAxis=trex_TranscendEnhanceSelectAndUniversalFasciaProductMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_ProductOrServiceAxis=trex_TrextrimAndTrexRevealRailingMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_ProductOrServiceAxis=trex_CommercialRailingAndStagingSystemsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongTermPurchaseCommitmentByCategoryOfItemPurchasedAxis=trex_RawMaterialSupplyContractsMember
Namespace Prefix:
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Commitments and Contingencies - Additional Information (Detail) $ in Millions		12 Months Ended
	Oct. 26, 2021 USD ($) a	Dec. 31, 2021 USD ($)
Schedule Of Commitments And Contingencies [Line Items]
Change in warranty reserve for disclosure purposes only		$ 1.9
Area of Land \| a	300
Residential Portfolio Segment [Member]
Schedule Of Commitments And Contingencies [Line Items]
Land and Land Improvements	$ 400.0
Land Improvements Term Period	5 years
Minimum [Member]
Schedule Of Commitments And Contingencies [Line Items]
Average period for PE material purchases under short-term supply contracts for which pricing is negotiated as needed		1 year
Maximum [Member]
Schedule Of Commitments And Contingencies [Line Items]
Average period for PE material purchases under short-term supply contracts for which pricing is negotiated as needed		2 years
Surface Flaking Warranty Reserve [Member]
Schedule Of Commitments And Contingencies [Line Items]
Percentage change in warranty claims used as a threshold for disclosure		10.00%
Residential Use [Member]
Schedule Of Commitments And Contingencies [Line Items]
Warranty period		25 years
Commercial Use [Member]
Schedule Of Commitments And Contingencies [Line Items]
Warranty period		10 years
Transcend Enhance Select And Universal Fascia Product [Member] \| Residential Use [Member]
Schedule Of Commitments And Contingencies [Line Items]
Warranty period		25 years
Transcend Enhance Select And Universal Fascia Product [Member] \| Commercial Use [Member]
Schedule Of Commitments And Contingencies [Line Items]
Warranty period		10 years
Trex Signature Railing [Member] \| Residential Use [Member]
Schedule Of Commitments And Contingencies [Line Items]
Warranty period		25 years
Trex Signature Railing [Member] \| Commercial Use [Member]
Schedule Of Commitments And Contingencies [Line Items]
Warranty period		25 years
Commercial Railing And Staging Systems [Member] \| Commercial Use [Member] \| Minimum [Member]
Schedule Of Commitments And Contingencies [Line Items]
Warranty period		1 year
Commercial Railing And Staging Systems [Member] \| Commercial Use [Member] \| Maximum [Member]
Schedule Of Commitments And Contingencies [Line Items]
Warranty period		3 years
Raw Material Supply Contracts [Member]
Schedule Of Commitments And Contingencies [Line Items]
Purchase commitment, due in second year		$ 47.0
Purchase commitment, due in third year		94.0
Purchase commitment, due in fourth year		$ 94.0