Cover Page - shares	3 Months Ended
	Mar. 31, 2020	May 06, 2020
Cover [Abstract]
Document Quarterly Report	true
Title of 12(b) Security	Class A common stock, par value $0.001 per share
Entity Incorporation, State or Country Code	DE
Entity Registrant Name	GNC Holdings, Inc.
Entity Central Index Key	0001502034
Document Type	10-Q
Entity File Number	001-35113
Document Period End Date	Mar. 31, 2020
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Shell Company	false
Entity Filer Category	Accelerated Filer
Entity Emerging Growth Company	false
Entity Small Business	false
Entity Common Stock, Shares Outstanding (in shares)		84,607,231
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q1
Entity Tax Identification Number	20-8536244
Entity Address, Address Line One	300 Sixth Avenue
Entity Address, Postal Zip Code	15222
Trading Symbol	GNC
Security Exchange Name	NYSE
City Area Code	412
Local Phone Number	288-4600
Document Transition Report	false
Entity Address, City or Town	Pittsburgh,
Entity Address, State or Province	PA