USANA Health Sciences, Inc. Quarterly report pursuant to Section 13 or 15(d)

Segment Information (Consolidated Net Sales And Long Lived Assets By Percent) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Apr. 04, 2015	Mar. 29, 2014
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales	$ 219,378us-gaap_SalesRevenueGoodsNet	$ 182,401us-gaap_SalesRevenueGoodsNet
China [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales	83,810	38,760
Long-lived Assets	83,316	81,704
United States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales	36,302	37,613
Long-lived Assets	56,779	53,322
Hong Kong [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales		$ 23,524