Note 3 - Commitments and Contingencies (Details Textual)
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1 Months Ended |
12 Months Ended |
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1 Months Ended |
3 Months Ended |
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Dec. 31, 2014
USD ($)
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Apr. 21, 2013
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Apr. 21, 2009
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Dec. 31, 2014
USD ($)
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Dec. 31, 2013
USD ($)
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Oct. 31, 2007
USD ($)
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Oct. 19, 2007
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Nov. 18, 2007
Five Year Warrants [Member]
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Oct. 31, 2007
One Year Warrants [Member]
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Dec. 31, 2007
Seven Year Warrants [Member]
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Dec. 31, 2014
Korean Business Segment [Member]
USD ($)
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Dec. 31, 2014
Korean Business Segment [Member]
KRW
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Commitments and Contingencies Disclosure [Abstract] |
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Operating Leases, Rent Expense |
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$ 777,000us-gaap_LeaseAndRentalExpense
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$ 787,000us-gaap_LeaseAndRentalExpense
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Purchase Commitment, Monthly Amount, Minimum |
40,000nhtc_PurchaseCommitmentMonthlyAmountMinimum
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40,000nhtc_PurchaseCommitmentMonthlyAmountMinimum
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Purchase Commitment, Remaining Minimum Amount Committed |
3,300,000us-gaap_PurchaseCommitmentRemainingMinimumAmountCommitted
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3,300,000us-gaap_PurchaseCommitmentRemainingMinimumAmountCommitted
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Purchase Commitment, Term |
3 years
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Purchase Commitment, Renewal Term |
3 years
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Supplemental Unemployment Benefits, Severance Benefits |
12,000us-gaap_SupplementalUnemploymentBenefitsSeveranceBenefits
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12,000us-gaap_SupplementalUnemploymentBenefitsSeveranceBenefits
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Other Assets, Noncurrent |
372,000us-gaap_OtherAssetsNoncurrent
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372,000us-gaap_OtherAssetsNoncurrent
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300,000us-gaap_OtherAssetsNoncurrent
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180,000us-gaap_OtherAssetsNoncurrent / us-gaap_NetAmountAtRiskByProductAndGuaranteeGuaranteeTypeAxis = nhtc_KoreanBusinessSegmentMember
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197,000,000us-gaap_OtherAssetsNoncurrent / us-gaap_NetAmountAtRiskByProductAndGuaranteeGuaranteeTypeAxis = nhtc_KoreanBusinessSegmentMember
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Convertible Debt |
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$ 4,250,000us-gaap_ConvertibleDebt
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Term Of Warrant |
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5 years
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1 year
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7 years
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7 years
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1 year
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7 years
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Class of Warrant or Right, Number of Securities Called by Warrants or Rights |
88,097us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights
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88,097us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights
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3,141,499us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights
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1,495,952us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights / us-gaap_RangeAxis = nhtc_FiveYearWarrantsMember
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1,495,952us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights / us-gaap_RangeAxis = nhtc_OneYearWarrantsMember
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1,495,952us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights / us-gaap_RangeAxis = nhtc_SevenYearWarrantsMember
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