Segment Information (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended																															12 Months Ended							12 Months Ended
	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010	Sep. 30, 2012 item	Sep. 30, 2011	Sep. 30, 2012 U.K.	Sep. 30, 2011 U.K.	Sep. 30, 2012 Netherlands	Sep. 30, 2011 Netherlands	Sep. 30, 2012 Ireland	Sep. 30, 2011 Ireland	Sep. 30, 2012 Canada	Sep. 30, 2011 Canada	Sep. 30, 2010 Predecessor	Sep. 30, 2010 Predecessor U.K.	Sep. 30, 2010 Predecessor Netherlands	Sep. 30, 2010 Predecessor Ireland	Sep. 30, 2010 Predecessor Canada	Sep. 30, 2012 Wholesale/U.S. Nutrition	Sep. 30, 2011 Wholesale/U.S. Nutrition	Sep. 30, 2010 Wholesale/U.S. Nutrition Predecessor	Sep. 30, 2012 European Retail	Sep. 30, 2011 European Retail	Sep. 30, 2012 European Retail Ireland item	Sep. 30, 2012 European Retail Holland & Barrett item	Sep. 30, 2012 European Retail Holland & Barrett Singapore item	Sep. 30, 2012 European Retail Holland & Barrett Cyprus item	Sep. 30, 2012 European Retail Holland & Barrett China item	Sep. 30, 2012 European Retail Holland & Barrett Malta item	Sep. 30, 2012 European Retail Holland & Barrett Gibraltar item	Sep. 30, 2012 European Retail Holland & Barrett Hungary item	Sep. 30, 2012 European Retail Holland & Barrett United Arab Emirates item	Sep. 30, 2012 European Retail GNC (UK) stores U.K. item	Sep. 30, 2012 European Retail De Tuinen Netherlands item	Sep. 30, 2010 European Retail Predecessor	Sep. 30, 2012 Direct Response/E-Commerce	Sep. 30, 2011 Direct Response/E-Commerce	Sep. 30, 2010 Direct Response/E-Commerce Predecessor	Sep. 30, 2012 North American Retail	Sep. 30, 2011 North American Retail	Sep. 30, 2012 North American Retail Vitamin World item	Sep. 30, 2010 North American Retail Predecessor	Sep. 30, 2012 Corporate/Manufacturing	Sep. 30, 2011 Corporate/Manufacturing	Sep. 30, 2010 Corporate/Manufacturing Predecessor
Segment Information
Number of business segments									4
Segment Information
Number of stores																													42	687								55	112							426
Number of franchised stores																															10	6	6	3	1	1	3		10
Net sales	$ 749,222	$ 782,316	$ 752,986	$ 715,209	$ 726,077	$ 740,897	$ 684,261	$ 713,192	$ 2,999,733	$ 2,864,427	$ 653,170	$ 596,927	$ 84,167	$ 80,221	$ 33,341	$ 33,774	$ 111,047	$ 95,639	$ 2,705,837	$ 516,200	$ 65,591	$ 24,567	$ 81,335	$ 1,826,780	$ 1,764,755	$ 1,734,860	$ 675,889	$ 636,303												$ 543,364	$ 277,278	$ 257,466	$ 233,972	$ 219,786	$ 205,903		$ 193,641
Income (loss) from continuing operations									394,370	237,321									355,273					241,504	283,775	292,991	151,274	121,219												101,121	56,391	59,193	68,018	22,812	12,575		11,272	(77,611)	(239,441)	(118,129)
Depreciation and amortization									102,271	99,675									63,346					39,692	38,840	14,578	13,988	13,277												10,705	10,704	10,649	4,698	2,996	2,997		2,032	34,891	33,912	31,333
Capital expenditures									$ 86,314	$ 43,999									$ 69,454					$ 804	$ 652	$ 1,473	$ 22,428	$ 19,338												$ 38,827	$ 131	$ 40	$ 36	$ 596	$ 955		$ 3,309	$ 62,355	$ 23,014	$ 25,809