Consolidated interest coverage ratio that must be maintained under the Credit Agreement.

No definition available.

Name:	nus_ConsolidatedInterestCoverageRatio
Namespace Prefix:	nus_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	duration

- Definition

Consolidated leverage ratio that must be maintained under the Credit Agreement.

+ References

No definition available.

+ Details

Name:	nus_ConsolidatedLeverageRatio
Namespace Prefix:	nus_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	duration

- Definition

The annual required amortization percentage applied to principal.

+ References

No definition available.

+ Details

Name:	nus_DebtInstrumentAnnualAmortizationPercentagePrincipal
Namespace Prefix:	nus_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28551-108399

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

+ Details

Name:	us-gaap_DebtInstrumentFaceAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Description of the frequency of periodic payments (monthly, quarterly, annual).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823

+ Details

Name:	us-gaap_DebtInstrumentFrequencyOfPeriodicPayment
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentTerm
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

Name:	us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- References

No definition available.

+ Details

Name:	us-gaap_LongtermDebtCurrentAndNoncurrentAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3255-108585

+ Details

Name:	us-gaap_ProceedsFromIssuanceOfLongTermDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

Name:	us-gaap_DebtInstrumentAxis=nus_CreditAgreementDated20180418Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=nus_TermLoanFacilityDated20180418Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentRedemptionPeriodAxis=us-gaap_DebtInstrumentRedemptionPeriodOneMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentRedemptionPeriodAxis=us-gaap_DebtInstrumentRedemptionPeriodTwoMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentRedemptionPeriodAxis=us-gaap_DebtInstrumentRedemptionPeriodThreeMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentRedemptionPeriodAxis=us-gaap_DebtInstrumentRedemptionPeriodFourMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentRedemptionPeriodAxis=us-gaap_DebtInstrumentRedemptionPeriodFiveMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableRateAxis=us-gaap_LondonInterbankOfferedRateLIBORMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=nus_RevolvingCreditFacilityDated20180418Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

DEBT, New Credit Agreement (Details) $ in Thousands		9 Months Ended
DEBT, New Credit Agreement (Details) $ in Thousands	Apr. 18, 2018 USD ($)	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)
Long-term Debt, Current and Noncurrent [Abstract]
Proceeds from debt		$ 582,398	$ 67,000
New Credit Agreement [Member] \| Maximum [Member]
Long-term Debt, Current and Noncurrent [Abstract]
Consolidated leverage ratio		2.25
New Credit Agreement [Member] \| Minimum [Member]
Long-term Debt, Current and Noncurrent [Abstract]
Consolidated interest coverage ratio		3.00
Term Loan Facility [Member]
Long-term Debt, Current and Noncurrent [Abstract]
Original principal amount	$ 400,000	$ 400,000
Term of loan		5 years
Frequency of payment		Quarterly
Term Loan Facility [Member] \| First Year [Member]
Long-term Debt, Current and Noncurrent [Abstract]
Annual amortization percentage	5.00%
Term Loan Facility [Member] \| Second Year [Member]
Long-term Debt, Current and Noncurrent [Abstract]
Annual amortization percentage	5.00%
Term Loan Facility [Member] \| Third Year [Member]
Long-term Debt, Current and Noncurrent [Abstract]
Annual amortization percentage	7.50%
Term Loan Facility [Member] \| Fourth Year [Member]
Long-term Debt, Current and Noncurrent [Abstract]
Annual amortization percentage	7.50%
Term Loan Facility [Member] \| Fifth Year [Member]
Long-term Debt, Current and Noncurrent [Abstract]
Annual amortization percentage	10.00%
Term Loan Facility [Member] \| LIBOR [Member]
Long-term Debt, Current and Noncurrent [Abstract]
Basis spread on variable rate	2.25%
Revolving Credit Facility [Member]
Long-term Debt, Current and Noncurrent [Abstract]
Borrowing capacity	$ 350,000
Term of loan		5 years
Proceeds from debt	$ 78,500
Revolving Credit Facility [Member] \| LIBOR [Member]
Long-term Debt, Current and Noncurrent [Abstract]
Basis spread on variable rate	2.25%