Segment Information (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013 item	Jun. 30, 2012
Segment Information
Number of business segments			4
Segment Information
Net sales	$ 802,829	$ 782,316	$ 2,349,930	$ 2,250,510
Income from operations	100,443	115,339	229,057	292,029
Depreciation and amortization	31,274	25,531	83,944	76,448
Capital expenditures	33,162	19,891	96,854	41,557
Restructuring charge	4,944		35,144
Wholesale
Segment Information
Net sales	489,227	480,138	1,429,103	1,373,560
Income from operations	65,995	74,043	162,886	180,355
Depreciation and amortization	9,171	8,930	27,319	26,808
Capital expenditures	177	131	407	632
European Retail
Segment Information
Net sales	191,692	176,460	557,779	522,590
Income from operations	45,478	41,748	127,979	116,759
Depreciation and amortization	3,544	3,209	10,405	9,490
Capital expenditures	7,494	6,946	21,412	16,210
European Retail \| Holland & Barrett
Segment Information
Number of stores	730		730
European Retail \| Holland & Barrett \| Singapore
Segment Information
Number of franchised stores	23		23
European Retail \| Holland & Barrett \| China
Segment Information
Number of franchised stores	23		23
European Retail \| Holland & Barrett \| United Arab Emirates
Segment Information
Number of franchised stores	7		7
European Retail \| Holland & Barrett \| Cyprus
Segment Information
Number of franchised stores	7		7
European Retail \| Holland & Barrett \| Malta
Segment Information
Number of franchised stores	4		4
European Retail \| Holland & Barrett \| Gibraltar
Segment Information
Number of franchised stores	1		1
European Retail \| Holland & Barrett \| Iceland
Segment Information
Number of franchised stores	1		1
European Retail \| Holland & Barrett \| Belgium
Segment Information
Number of franchised stores	13		13
European Retail \| GNC (UK) stores \| U.K.
Segment Information
Number of stores	57		57
European Retail \| De Tuinen \| Netherlands
Segment Information
Number of stores	122		122
Number of franchised stores	7		7
European Retail \| Nature's Way \| Ireland
Segment Information
Number of stores	47		47
Direct Response / E-Commerce
Segment Information
Net sales	63,670	66,369	186,252	179,912
Income from operations	9,001	13,749	32,325	35,807
Depreciation and amortization	2,506	2,662	7,515	7,980
Capital expenditures	2,280	81	3,048	81
North American Retail
Segment Information
Net sales	58,240	59,349	176,796	174,448
Income from operations	7,247	7,336	19,995	18,356
Depreciation and amortization	609	716	1,851	2,319
Capital expenditures	1,475	215	2,900	503
North American Retail \| Vitamin World
Segment Information
Number of stores	423		423
Corporate/Manufacturing
Segment Information
Income from operations	(27,278)	(21,537)	(114,128)	(59,248)
Depreciation and amortization	15,444	10,014	36,854	29,851
Capital expenditures	21,736	12,518	69,087	24,131
Restructuring charge	$ 4,944		$ 35,144

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