Segment Information (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Dec. 31, 2014 segment	Dec. 31, 2013
Segment Information
Number of business segments	4us-gaap_NumberOfReportableSegments
Segment Information
Net sales	$ 825,771us-gaap_SalesRevenueGoodsNet	$ 827,105us-gaap_SalesRevenueGoodsNet
Income (loss) from operations	95,525us-gaap_OperatingIncomeLoss	114,181us-gaap_OperatingIncomeLoss
Depreciation and amortization	28,065	25,566
Capital expenditures	19,090	21,247
Reportable Business Segments
Segment Information
Net sales	825,771	827,105
Income (loss) from operations	118,508	136,455
Depreciation and amortization	17,776	16,648
Capital expenditures	11,812	9,555
Corporate/Manufacturing
Segment Information
Income (loss) from operations	(22,983)	(22,274)
Depreciation and amortization	10,289	8,918
Capital expenditures	7,278	11,692
Wholesale segment \| Reportable Business Segments
Segment Information
Net sales	495,126	505,275
Income (loss) from operations	64,829	82,728
Depreciation and amortization	9,002	9,086
Capital expenditures	73	31
European Retail \| Reportable Business Segments
Segment Information
Net sales	213,597	204,912
Income (loss) from operations	46,315	43,960
Depreciation and amortization	5,049	4,044
Capital expenditures	10,703	5,321
European Retail \| Reportable Business Segments \| Holland & Barrett
Segment Information
Number of stores	766
European Retail \| Reportable Business Segments \| Holland & Barrett \| China
Segment Information
Number of franchised stores	31
European Retail \| Reportable Business Segments \| Holland & Barrett \| Singapore
Segment Information
Number of franchised stores	30
European Retail \| Reportable Business Segments \| Holland & Barrett \| United Arab Emirates
Segment Information
Number of franchised stores	12
European Retail \| Reportable Business Segments \| Holland & Barrett \| Cyprus
Segment Information
Number of franchised stores	10
European Retail \| Reportable Business Segments \| Holland & Barrett \| Malta
Segment Information
Number of franchised stores	5
European Retail \| Reportable Business Segments \| Holland & Barrett \| Gibraltar
Segment Information
Number of franchised stores	1
European Retail \| Reportable Business Segments \| Holland & Barrett \| Iceland
Segment Information
Number of franchised stores	1
European Retail \| Reportable Business Segments \| Holland & Barrett \| Kuwait
Segment Information
Number of franchised stores	1
European Retail \| Reportable Business Segments \| De Tuinen \| Netherlands
Segment Information
Number of stores	148
Number of franchised stores	6
European Retail \| Reportable Business Segments \| GNC (UK) stores \| U.K.
Segment Information
Number of stores	53
European Retail \| Reportable Business Segments \| GNC (UK) stores \| Ireland
Segment Information
Number of stores	48
European Retail \| Reportable Business Segments \| GNC (UK) stores \| Belgium
Segment Information
Number of stores	17
Direct Response / E-Commerce \| Reportable Business Segments
Segment Information
Net sales	63,143	60,362
Income (loss) from operations	6,060	6,975
Depreciation and amortization	2,830	2,812
Capital expenditures	13	570
North American Retail \| Reportable Business Segments
Segment Information
Net sales	53,905	56,556
Income (loss) from operations	1,304	2,792
Depreciation and amortization	895	706
Capital expenditures	$ 1,023	$ 3,633
North American Retail \| Reportable Business Segments \| Vitamin World
Segment Information
Number of stores	403

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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