Document and Entity Information (USD $)	12 Months Ended
	Sep. 30, 2013	Nov. 18, 2013	Mar. 31, 2013
Document and Entity Information
Entity Registrant Name	LIQUIDITY SERVICES INC
Entity Central Index Key	0001235468
Document Type	10-K
Document Period End Date	Sep. 30, 2013
Amendment Flag	false
Current Fiscal Year End Date	--09-30
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Public Float			$ 744,335,757
Entity Common Stock, Shares Outstanding		32,124,703
Document Fiscal Year Focus	2013
Document Fiscal Period Focus	FY