v3.3.0.814

Document and Entity Information - shares	9 Months Ended
Document and Entity Information - shares	Sep. 30, 2015	Nov. 03, 2015
Document And Entity Information [Abstract]
Entity Registrant Name	Energy Future Intermediate Holding CO LLC
Entity Central Index Key	0001445146
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Document Type	10-Q
Document Period End Date	Sep. 30, 2015
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	Q3
Amendment Flag	false
Entity Common Stock, Shares Outstanding		0
Entity Outstanding Membership Interests	At November 3, 2015, the outstanding membership interest in Energy Future Intermediate Holding Company LLC was directly held by Energy Future Holdings Corp.

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End date of current fiscal year in the format --MM-DD.

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This is focus fiscal year of the document report in CCYY format. For a 2006 annual report, which may also provide financial information from prior periods, fiscal 2006 should be given as the fiscal year focus. Example: 2006.

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The end date of the period reflected on the cover page if a periodic report. For all other reports and registration statements containing historical data, it is the date up through which that historical data is presented. If there is no historical data in the report, use the filing date. The format of the date is CCYY-MM-DD.

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The type of document being provided (such as 10-K, 10-Q, 485BPOS, etc). The document type is limited to the same value as the supporting SEC submission type, or the word "Other".

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A unique 10-digit SEC-issued value to identify entities that have filed disclosures with the SEC. It is commonly abbreviated as CIK.

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

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Document and Entity Information Abstract

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Energy Future Intermediate Holding CO LLC 10-Q