Document and Entity Information - USD ($) $ in Billions	12 Months Ended
	Feb. 01, 2020	Mar. 23, 2020	Aug. 03, 2019
Cover [Abstract]
Entity Registrant Name	Ollie's Bargain Outlet Holdings, Inc.
Entity Central Index Key	0001639300
Current Fiscal Year End Date	--02-01
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Shell Company	false
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Public Float			$ 4.4
Entity Common Stock, Shares Outstanding		63,749,400
Document Type	10-K
Amendment Flag	false
Document Period End Date	Feb. 01, 2020
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	FY
Document Annual Report	true
Document Transition Report	false
Entity File Number	001-37501
Entity Tax Identification Number	80-0848819
Entity Incorporation, State or Country Code	DE
Entity Address, Address Line One	6295 Allentown Boulevard
Entity Address, Address Line Two	Suite 1
Entity Address, City or Town	Harrisburg
Entity Address, State or Province	PA
Entity Address, Postal Zip Code	17112
City Area Code	717
Local Phone Number	657-2300
Title of 12(b) Security	Common Stock, $0.001 par value
Trading Symbol	OLLI
Security Exchange Name	NASDAQ