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us-gaap_LiabilitiesCurrent Total current liabilities Adjustments to reconcile net income to net cash used in operating activities: Reclassification out of Accumulated Other Comprehensive Income [Member] Reclassification out of Accumulated Other Comprehensive Income [Domain] Reclassification out of Accumulated Other Comprehensive Income [Axis] Comprehensive Income (Loss) Note [Text Block] Fair Value, Inputs, Level 2 [Member] Fair Value, Inputs, Level 1 [Member] Fair Value Hierarchy [Domain] Fair Value, Hierarchy [Axis] Fair Value, Inputs, Level 3 [Member] Geographic Concentration Risk [Member] Customer Concentration Risk [Member] Concentration Risk Type [Axis] us-gaap_OtherIncome Other Income Concentration Risk Type [Domain] us-gaap_NumberOfReportableSegments Number of Reportable Segments Building and Building Improvements [Member] Foreign exchange gain (loss) Leasehold Improvements [Member] Pension expense Property, Plant and Equipment, Type [Axis] Property, Plant and Equipment, Type 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Entity Common Stock, Shares Outstanding (in shares) Equity Components [Axis] us-gaap_LineOfCreditFacilityCurrentBorrowingCapacity Line of Credit Facility, Current Borrowing Capacity us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity Line of Credit Facility, Maximum Borrowing Capacity Accounts receivable, allowance for doubtful accounts Accounts receivable - less allowance for doubtful accounts of $16 at December 31, 2014 and $94 at June 30, 2014 Equity Component [Domain] Other comprehensive income before reclassifications us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodBeforeTax Amounts reclassified from OCI Employee Stock Option [Member] us-gaap_LineOfCreditFacilityCommitmentFeeAmount Line of Credit Facility, Commitment Fee Amount us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount us-gaap_TreasuryStockSharesAcquired Treasury Stock, Shares, Acquired Change in unrealized gain resulting from change in fair value of derivative instruments, net of tax The change during the period in an unrealized gain (loss) on derivatives. 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Customer 3 [Member] Customer 3 in a set of customers. us-gaap_TreasuryStockAcquiredAverageCostPerShare Treasury Stock Acquired, Average Cost Per Share Selling, general and administrative expenses Natural Alternatives International Europe SA [Member] The entity Natural alternatives international Europe SA. Increase (decrease) in provision for uncollectible accounts receivable us-gaap_IncreaseDecreaseInIncomeTaxes Income taxes Property and equipment us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment Less: accumulated depreciation and amortization Amended Line of Credit Facility [Member] A line of credit facility that has been amended from its original terms. 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Markets Outside the United States [Member] Markets located outside of the United States. Private Label Contract Manufacturing [Member] Business segment related to private label contract manufacturing. Award Type [Axis] us-gaap_Revenues Revenues Sales Revenue, Net [Member] us-gaap_OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax Concentration Risk Benchmark [Axis] Concentration Risk Benchmark [Domain] Pension and Other Postretirement Benefits Disclosure [Text Block] Compensation and Retirement Disclosure [Abstract] Other Noncurrent Assets Net [Member] Non current assets not otherwise defined. Unrealized gain (loss) resulting from change in fair value of derivative instruments, net of tax Cash Flow Hedging Foreign Exchange Contract [Member] A foreign currency derivative designated as cash flow hedging instruments. 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Cash flows from financing activities Segments [Axis] Statement [Table] us-gaap_NetCashProvidedByUsedInInvestingActivities Net cash used by investing activities us-gaap_AllocatedShareBasedCompensationExpense Allocated Share-based Compensation Expense Customer 4 [Member] Customer 4 [member Scenario, Unspecified [Domain] Income Tax Disclosure [Text Block] Preferred stock par value (in dollars per share) Scenario [Axis] Net Sales and Income From Operations [Member] Represents net sales and income from operations. 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