XML 42 R40.htm IDEA: XBRL DOCUMENT
v3.19.3.a.u2

Summary Of Significant Accounting Policies (Schedule Of Contract Liabilities From Contract With Customers) (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 28, 2019 | Dec. 29, 2018
Summary Of Significant Accounting Policies [Abstract] |  |
Contract liabilities at beginning of period | $ 15,055 | $ 14,417
Increase due to deferral of revenue at period end | 13,852 | 15,055
Decrease due to beginning contract liabilities recognized as revenue | (15,055) | (14,417)
Contract liabilities at end of period | $ 13,852 | $ 15,055

X
- References No definition available. + Details
Name: | us-gaap_AccountingPoliciesAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=118944033&loc=SL49130531-203044 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130549-203045 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=118944033&loc=SL49130532-203044 + Details
Name: | us-gaap_ContractWithCustomerLiability
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Contract with Customer, Liability, Increase (Decrease) In Deferred Revenue + References No definition available. + Details
Name: | usna_ContractWithCustomerLiabilityIncreaseDecreaseInDeferredRevenue
Namespace Prefix: | usna_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Contract with Customer, Liability, Increase (Decrease) Revenue Recognized + References No definition available. + Details
Name: | usna_ContractWithCustomerLiabilityIncreaseDecreaseRevenueRecognized
Namespace Prefix: | usna_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration