Document and Entity Information (USD $)	12 Months Ended
	Dec. 31, 2012	Mar. 28, 2013 Managing general partner	Mar. 28, 2013 Limited partners
Entity Registrant Name	Reef Global Energy VII, L.P.
Entity Central Index Key	0001344530
Document Type	10-K
Document Period End Date	Dec. 31, 2012
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Smaller Reporting Company
Entity Common Stock, Shares Outstanding		48.620	923.784
Entity Public Float	$ 0
Document Fiscal Year Focus	2012
Document Fiscal Period Focus	FY