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Stock-Based Compensation - Summary of Stock-Based Compensation Grants (Detail) | 3 Months Ended
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Mar. 31, 2019 $ / shares shares
Time Based Restricted Stock Units [Member] |
Stock Awards Granted | shares | 26,158
Weighted-Average Grant Price Per Share | $ / shares | $ 77.61
Performance Based Restricted Stock Units [Member] |
Stock Awards Granted | shares | 80,104
Weighted-Average Grant Price Per Share | $ / shares | $ 47.89
Stock Appreciation Rights [Member] |
Stock Awards Granted | shares | 24,536
Weighted-Average Grant Price Per Share | $ / shares | $ 77.70

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- Definition Share based compensation arrangement by share based payment award non options equity instruments granted weighted average grant price. + References No definition available. + Details
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Namespace Prefix: | trex_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | duration

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- Definition The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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Data Type: | xbrli:sharesItemType
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Period Type: | duration

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- Details
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- Details
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- Details
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