Goodwill and Intangible Assets - Goodwill (Details) $ in Thousands	3 Months Ended
	Dec. 31, 2015 USD ($)
Changes in goodwill
Balance at the beginning of the period	$ 1,104,090
Acquisition of Dr. Organic Limited	94,399
Foreign currency translation	(11,918)
Balance at the end of the period	1,186,571
Consumer Products Group
Changes in goodwill
Balance at the beginning of the period	611,678
Acquisition of Dr. Organic Limited	94,399
Foreign currency translation	(4,747)
Balance at the end of the period	701,330
Holland & Barrett International
Changes in goodwill
Balance at the beginning of the period	293,381
Foreign currency translation	(7,171)
Balance at the end of the period	286,210
Puritan's Pride
Changes in goodwill
Balance at the beginning of the period	199,031
Balance at the end of the period	199,031
Adjustment
Changes in goodwill
Balance at the beginning of the period	(13,930)
Balance at the end of the period	(13,930)
Adjustment | Consumer Products Group
Changes in goodwill
Balance at the end of the period	(7,129)
Adjustment | Holland & Barrett International
Changes in goodwill
Balance at the end of the period	(3,086)
Adjustment | Puritan's Pride
Changes in goodwill
Balance at the end of the period	$ (3,715)