SCHEDULE I - CONDENSED FINANCIAL INFORMATION OF GNC HOLDINGS, INC. - Statements of Cash Flows (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Cash flows from operating activities:
Net (loss) income	$ (209,825)	$ 21,463	$ 15,661	$ 23,850	$ (433,447)	$ 32,354	$ 64,028	$ 50,815	$ (148,851)	$ (286,250)	$ 219,299
Other operating activities									4,751	2,164	5,298
Net cash provided by operating activities									220,508	208,198	354,533
Cash flows from financing activities:
Proceeds from exercise of stock options									0	353	1,743
Minimum tax withholding requirements									(253)	(1,169)	(574)
Repurchase of treasury stock									0	(229,169)	(479,799)
Dividend payment									0	(55,336)	(59,647)
Net cash used in financing activities									(168,106)	(207,536)	(384,458)
Net increase (decrease) in cash and cash equivalents									29,537	(21,998)	(77,372)
Beginning balance, cash and cash equivalents				34,464				56,462	34,464	56,462	133,834
Ending balance, cash and cash equivalents	64,001				34,464				64,001	34,464	56,462
GNC Holdings
Cash flows from operating activities:
Net (loss) income									(148,851)	(286,250)	219,299
Deficit (Equity) in loss (income) of subsidiaries									161,463	279,192	(223,090)
Dividends received									0	283,280	422,355
Other operating activities									(12,339)	10,895	4,738
Net cash provided by operating activities									273	287,117	423,302
Cash flows from financing activities:
Loan to a subsidiary									0	0	(164,300)
Proceeds from issuance of convertible notes									0	0	287,500
Debt issuance costs on convertible senior notes									0	(1,797)	(8,225)
Proceeds from exercise of stock options									0	353	1,744
Minimum tax withholding requirements									(253)	(1,169)	(574)
Repurchase of treasury stock									0	(229,169)	(479,799)
Dividend payment									0	(55,336)	(59,648)
Net cash used in financing activities									(253)	(287,118)	(423,302)
Net increase (decrease) in cash and cash equivalents									20	(1)	0
Beginning balance, cash and cash equivalents				$ 0				$ 1	0	1	1
Ending balance, cash and cash equivalents	$ 20				$ 0				$ 20	$ 0	$ 1