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Schedule of commitments and contingencies.

No definition available.

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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.

No definition available.

Name:	trex_SensitivityChangeInSurfaceFlakingWarrantyReserve
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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

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

No definition available.

Name:	trex_WarrantyPeriod
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Area of land held.

No definition available.

Name:	us-gaap_AreaOfLand
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Amount before accumulated depreciation 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.

Reference 1: 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 https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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