USANA Health Sciences, Inc. Annual report pursuant to Section 13 and 15(d)

Valuation And Qualifying Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016
Allowance For Sale Returns [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at beginning of period	$ 632	$ 696	$ 521
Charged to costs and expenses	307	44	213
Charged to other accounts
Deductions	100	108	38
Balance at end of period	839	632	696
Allowance For Doubtful Accounts [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at beginning of period	325	743	1,936
Charged to costs and expenses	8	14	220
Charged to other accounts
Deductions	194	432	1,413
Balance at end of period	139	325	743
Valuation Allowance - Deferred Tax Assets [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at beginning of period	13,980	640	607
Charged to costs and expenses	30,219	13,340	33
Charged to other accounts
Balance at end of period	$ 44,199	$ 13,980	$ 640