Quarterly report pursuant to Section 13 or 15(d)

Income Taxes (Details)

v2.4.1.9
Income Taxes (Details) (USD $)
In Thousands, unless otherwise specified
3 Months Ended 12 Months Ended
Mar. 31, 2015
Mar. 31, 2014
Dec. 31, 2014
Income Taxes      
Provision (benefit) for income taxes, as a percentage of income before income taxes 16.10%us-gaap_EffectiveIncomeTaxRateContinuingOperations (55.60%)us-gaap_EffectiveIncomeTaxRateContinuingOperations  
Statutory U.S. federal income tax rate (as a percent) 35.00%us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate   35.00%us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate
Intercompany dividends paid by foreign subsidiaries to the U.S. corporation.   $ 21,500natr_IntercompanyDividendsPaidByForeignSubsidiaries  
Income tax benefit   6,720natr_DiscreteIncomeTaxExpenseBenefit  
Accrued amount related to unrecognized tax positions $ 6,776us-gaap_UnrecognizedTaxBenefits   $ 6,598us-gaap_UnrecognizedTaxBenefits