Annual report pursuant to Section 13 and 15(d)

Derivative Instruments and Hedging Activities - Gains (Losses) Relating to Derivative Instruments Recorded in Other Comprehensive Income (Loss) (Detail)

v2.4.1.9
Derivative Instruments and Hedging Activities - Gains (Losses) Relating to Derivative Instruments Recorded in Other Comprehensive Income (Loss) (Detail) (Derivatives designated as hedging instruments [Member], USD $)
In Millions, unless otherwise specified
12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Foreign exchange currency contracts relating to inventory and intercompany management fee hedges [Member]      
Derivative Instruments, Gain (Loss) [Line Items]      
Amount of Gain (Loss) Recognized in Other Comprehensive Income (Loss) $ 16.8us-gaap_DerivativeInstrumentsGainLossRecognizedInOtherComprehensiveIncomeEffectivePortionNet
/ us-gaap_DerivativeInstrumentRiskAxis
= hlf_ForeignExchangeCurrencyContractsRelatingToInventoryHedgesAndIntercompanyManagementFeeHedgesMember
/ us-gaap_HedgingDesignationAxis
= us-gaap_DesignatedAsHedgingInstrumentMember
$ 3.5us-gaap_DerivativeInstrumentsGainLossRecognizedInOtherComprehensiveIncomeEffectivePortionNet
/ us-gaap_DerivativeInstrumentRiskAxis
= hlf_ForeignExchangeCurrencyContractsRelatingToInventoryHedgesAndIntercompanyManagementFeeHedgesMember
/ us-gaap_HedgingDesignationAxis
= us-gaap_DesignatedAsHedgingInstrumentMember
$ (3.3)us-gaap_DerivativeInstrumentsGainLossRecognizedInOtherComprehensiveIncomeEffectivePortionNet
/ us-gaap_DerivativeInstrumentRiskAxis
= hlf_ForeignExchangeCurrencyContractsRelatingToInventoryHedgesAndIntercompanyManagementFeeHedgesMember
/ us-gaap_HedgingDesignationAxis
= us-gaap_DesignatedAsHedgingInstrumentMember
Interest rate swaps [Member]      
Derivative Instruments, Gain (Loss) [Line Items]      
Amount of Gain (Loss) Recognized in Other Comprehensive Income (Loss)     $ (0.6)us-gaap_DerivativeInstrumentsGainLossRecognizedInOtherComprehensiveIncomeEffectivePortionNet
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_InterestRateSwapMember
/ us-gaap_HedgingDesignationAxis
= us-gaap_DesignatedAsHedgingInstrumentMember