The amount of deferred tax assets realized during the period that were previously reserved under a valuation allowance.

No definition available.

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- Definition

Amount of increase (decrease) in additional paid in capital (APIC) resulting from a tax benefit (deficiency) associated with an share-based compensation plan other than an employee stock ownership plan (ESOP).

+ References

No definition available.

+ Details

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- Definition

Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32537-109319

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- Definition

Tax year being audited in the income tax examination, in CCYY format.

+ References

No definition available.

+ Details

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- Definition

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(h))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph h

-Article 4

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Income Tax Expense (or Benefit)

-URI http://asc.fasb.org/extlink&oid=6515339

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 9

-Subparagraph (a),(b)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32639-109319

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- Definition

Tax year that remains open to examination under enacted tax laws, in CCYY format.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (e)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32718-109319

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- Definition

Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Unrecognized Tax Benefit

-URI http://asc.fasb.org/extlink&oid=6527854

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15A

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319

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Income Taxes - Additional Information (Detail) (USD $)	12 Months Ended			3 Months Ended
Income Taxes - Additional Information (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2013
Income Tax Examination [Line Items]
Deferred tax assets previously reserved under a valuation allowance		$ 9,100,000trex_DeferredTaxAssetsRealized		$ 9,100,000trex_DeferredTaxAssetsRealized
Valuation allowance	4,465,000	4,201,000		4,201,000
Provision (benefit) for income taxes	25,427,000us-gaap_IncomeTaxExpenseBenefit	(10,549,000)us-gaap_IncomeTaxExpenseBenefit	1,009,000us-gaap_IncomeTaxExpenseBenefit
Excess tax benefits from stock compensation	12,883,000	1,466,000
Unrecognized tax benefits related to identified uncertain tax positions	0us-gaap_UnrecognizedTaxBenefits
Exit Full Valuation Allowance [Member]
Income Tax Examination [Line Items]
Provision (benefit) for income taxes				$ 10,900,000
Earliest Tax Year [Member] \| Federal Tax Jurisdiction [Member]
Income Tax Examination [Line Items]
Tax years subject to examination	2011
Earliest Tax Year [Member] \| Michigan [Member]
Income Tax Examination [Line Items]
Tax years examined	2008
Latest Tax Year [Member] \| Federal Tax Jurisdiction [Member]
Income Tax Examination [Line Items]
Tax years subject to examination	2013
Latest Tax Year [Member] \| Michigan [Member]
Income Tax Examination [Line Items]
Tax years examined	2011