v2.4.0.6

Document and Entity Information (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Mar. 30, 2012
Document and Entity Information [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2011
Entity Registrant Name	Ridgewood Energy L Fund LLC
Entity Central Index Key	0001295714
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2011
Document Fiscal Period Focus	FY
Entity Filer Category	Smaller Reporting Company
Entity Common Stock, Shares Outstanding		350.1081
Entity Current Reporting Status	Yes
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Public Float	$ 0

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State aggregate market value of voting and non-voting common equity held by non-affiliates computed by reference to price at which the common equity was last sold, or average bid and asked price of such common equity, as of the last business day of registrant's most recently completed second fiscal quarter. The public float should be reported on the cover page of the registrants form 10K.

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The exact name of the entity filing the report as specified in its charter, which is required by forms filed with the SEC.

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Ridgewood Energy L Fund LLC 10-K