Document and Entity Information (USD $)	12 Months Ended
	Dec. 31, 2012
Document and Entity Information [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2012
Document Fiscal Year Focus	2012
Document Fiscal Period Focus	FY
Entity Registrant Name	Atlas Resources Public #18-2009 (B) L.P.
Entity Central Index Key	0001432985
Current Fiscal Year End Date	--12-31
Entity Filer Category	Smaller Reporting Company
Entity Common Stock, Shares Outstanding	12,278
Entity Current Reporting Status	Yes
Entity Public Float	$ 0
Entity Voluntary Filers	No
Entity Well-known Seasoned Issuer	No