Risk/Return Summary [Abstract] index_JPMorgan_Emerging_Market_Bond_Index_Global_Diversified_Index_reflects_no_deduction_for_fees_expenses_or_taxes JPMorgan Emerging Market Bond Index Global Diversified® Index (reflects no deduction for fees, expenses or taxes) index_JP_Morgan_Emerging_Local_Markets_Index_Plus_reflects_no_deduction_for_fees_expenses_or_taxes JP Morgan Emerging Local Markets Index Plus (reflects no deduction for fees, expenses or taxes) index_Barclays_Capital_Global_Aggregate_Bond_Index_reflects_no_deduction_for_fees_expenses_or_taxes Barclays Capital Global Aggregate Bond Index (reflects no deduction for fees, expenses or taxes) index_Custom_Infrastructure_Index_Hedged_reflects_no_deduction_for_fees_expenses_or_taxes Custom Infrastructure Index (Hedged) (reflects no deduction for fees, expenses or taxes) index_HFRX_Equity_Hedge_Index_reflects_no_deduction_for_fees_expenses_or_taxes HFRX Equity Hedge Index (reflects no deduction for fees, expenses or taxes) index_Russell_2500_Index_reflects_no_deduction_for_fees_expenses_or_taxes_Open Russell 2500 Index (reflects no deduction for fees, expenses or taxes) (Open) index_MSCI_EAFE_Index_reflects_no_deduction_for_fees_expenses_or_taxes_Open MSCI EAFE Index (reflects no deduction for fees, expenses or taxes) (Open) index_MSCI_World_Index_reflects_no_deduction_for_fees_expenses_or_taxes_Institutional MSCI World Index (reflects no deduction for fees, expenses or taxes) (Institutional) index_MSCI_EAFE_Index_reflects_no_deduction_for_fees_expenses_or_taxes_Institutional MSCI EAFE Index (reflects no deduction for fees, expenses or taxes) (Institutional) index_Russell_20002500_Linked_Index_reflects_no_deduction_for_fees_expenses_or_taxes_Institutional Russell 2000/2500 Linked Index (reflects no deduction for fees, expenses or taxes) (Institutional) index_MSCI_All_Country_World_Index_reflects_no_deduction_for_fees_expenses_or_taxes MSCI All Country World Index (reflects no deduction for fees, expenses or taxes) index_SP_500_Index_reflects_no_deduction_for_fees_expenses_or_taxes S&P 500 Index (reflects no deduction for fees, expenses or taxes) index_MSCI_All_Country_World_Index_exUS_reflects_no_deduction_for_fees_expenses_or_taxes MSCI All Country World Index ex-US (reflects no deduction for fees, expenses or taxes) index_MSCI_EAFE_Small_Cap_Index_reflects_no_deduction_for_fees_expenses_or_taxes_Open MSCI EAFE Small Cap Index (reflects no deduction for fees, expenses or taxes) (Open) index_FTSE_NAREIT_All_Equity_REITs_Index_reflects_no_deduction_for_fees_expenses_or_taxes_Open FTSE NAREIT All Equity REITs Index (reflects no deduction for fees, expenses or taxes) (Open) index_FTSE_EPRANAREIT_Global_exUSFTSENAREIT_Global_Linked_Index_reflects_no_deduction_for_fees_expenses_or_taxes_Open FTSE EPRA/NAREIT Global ex-US/FTSE/NAREIT Global Linked Index (reflects no deduction for fees, expenses or taxes) (Open) index_HFRX_Global_Hedge_Fund_Index_reflects_no_deduction_for_fees_expenses_or_taxes HFRX Global Hedge Fund Index (reflects no deduction for fees, expenses or taxes) index_MSCI_Emerging_Markets_Index_reflects_no_deduction_for_fees_expenses_or_taxes_R6 MSCI Emerging Markets Index (reflects no deduction for fees, expenses or taxes) (R6) index_MSCI_Emerging_Markets_Index_reflects_no_deduction_for_fees_expenses_or_taxes_Institutional MSCI Emerging Markets Index (reflects no deduction for fees, expenses or taxes) (Institutional) index_Global_Asset_Allocation_Blended_Index_reflects_no_deduction_for_fees_expenses_or_taxes_Institutional Global Asset Allocation Blended Index (reflects no deduction for fees, expenses or taxes) (Institutional) index_SP_500_Index_reflects_no_deductions_for_fees_expenses_or_taxes_Institutional S&P 500 Index (reflects no deductions for fees, expenses or taxes) (Institutional) index_Bank_of_America_Merrill_Lynch_BBB_US_Cash_Pay_NonDistressed_High_Yield_Index_reflects_no_deduction_for_fees_expenses_or_taxes_Institutional Bank of America Merrill Lynch BB-B US Cash Pay Non-Distressed High Yield Index (reflects no deduction for fees, expenses or taxes) (Institutional) index_Russell_Midcap_Index_reflects_no_deduction_for_fees_expenses_or_taxes Russell Midcap Index (reflects no deduction for fees, expenses or taxes) index_MSCI_World_Index_reflects_no_deduction_for_fees_expenses_or_taxes MSCI World Index (reflects no deduction for fees, expenses or taxes) index_FTSE_EPRANAREIT_Global_exUSFTSENAREIT_Global_Linked_Index_reflects_no_deduction_for_fees_expenses_or_taxes_Institutional FTSE EPRA/NAREIT Global ex-US/FTSE/NAREIT Global Linked Index (reflects no deduction for fees, expenses or taxes) (Institutional) index_FTSE_NAREIT_All_Equity_REITs_Index_reflects_no_deduction_for_fees_expenses_or_taxes_Institutional FTSE NAREIT All Equity REITs Index (reflects no deduction for fees, expenses or taxes) (Institutional) index_Wells_Fargo_Hybrid_and_Preferred_Securities_REIT_Index_reflects_no_deduction_for_fees_expenses_or_taxes_Open Wells Fargo Hybrid and Preferred Securities REIT Index (reflects no deduction for fees, expenses or taxes) (Open) index_Bank_of_America_Merrill_Lynch_13_Year_US_Treasury_Index_reflects_no_deduction_for_fees_expenses_or_taxes Bank of America Merrill Lynch 1-3 Year US Treasury Index (reflects no deduction for fees, expenses or taxes) index_FTSE_EPRANAREIT_Global_Index_reflects_no_reduction_for_fees_expenses_or_taxes_Open FTSE EPRA/NAREIT Global Index (reflects no reduction for fees, expenses or taxes) (Open) index_Global_Asset_Allocation_Blended_Index_reflects_no_deduction_for_fees_expenses_or_taxes_Open Global Asset Allocation Blended Index (reflects no deduction for fees, expenses or taxes) (Open) index_JPMorgan_Government_Bond_Index_Emerging_Markets_Global_Diversified_Index_reflects_no_deduction_for_fees_expenses_or_taxes JPMorgan Government Bond Index – Emerging Markets Global Diversified® Index (reflects no deduction for fees, expenses or taxes) index_MSCI_EAFEAll_Country_World_Index_exUS_Linked_Index_reflects_no_deduction_for_fees_expenses_or_taxes MSCI EAFE/All Country World Index ex-US Linked Index (reflects no deduction for fees, expenses or taxes) index_SP_500_Index_reflects_no_deductions_for_fees_expenses_or_taxes_Open S&P 500 Index (reflects no deductions for fees, expenses or taxes) (Open) index_MSCI_Emerging_Markets_Index_reflects_no_deduction_for_fees_expenses_or_taxes_Open MSCI Emerging Markets Index (reflects no deduction for fees, expenses or taxes) (Open) index_SP_500_Index_reflects_no_deduction_for_fees_expenses_or_taxes_R6 S&P 500 Index (reflects no deduction for fees, expenses or taxes) (R6) index_FTSE_EPRANAREIT_Global_Index_reflects_no_reduction_for_fees_expenses_or_taxes_Institutional FTSE EPRA/NAREIT Global Index (reflects no reduction for fees, expenses or taxes) (Institutional) index_MSCI_EAFE_Index_reflects_no_deduction_for_fees_expenses_or_taxes_R6 MSCI EAFE Index (reflects no deduction for fees, expenses or taxes) (R6) index_50_FTSE_NAREIT_All_Equity_REITs_Index50_Wells_Fargo_Hybrid_and_Preferred_Securities_REIT_Index_reflects_no_deduction_for_fees_expenses_or_taxes_Institutional 50% FTSE NAREIT All Equity REITs Index/50% Wells Fargo Hybrid and Preferred Securities REIT Index (reflects no deduction for fees, expenses or taxes) (Institutional) index_Wells_Fargo_Hybrid_and_Preferred_Securities_REIT_Index_reflects_no_deduction_for_fees_expenses_or_taxes_Institutional Wells Fargo Hybrid and Preferred Securities REIT Index (reflects no deduction for fees, expenses or taxes) (Institutional) index_Russell_2500_Index_reflects_no_deduction_for_fees_expenses_or_taxes_Institutional Russell 2500 Index (reflects no deduction for fees, expenses or taxes) (Institutional) index_MSCI_EAFE_Small_Cap_Index_reflects_no_deduction_for_fees_expenses_or_taxes_Institutional MSCI EAFE Small Cap Index (reflects no deduction for fees, expenses or taxes) (Institutional) index_50_JPMorgan_Emerging_Market_Bond_Index_Global_Diversified_Index_50_JPMorgan_Government_Bond_Index_Emerging_Markets_Global_Diversified_Index_reflects_no_deduction_for_fees_expenses_or_taxes 50% JPMorgan Emerging Market Bond Index Global Diversified Index/ 50% JPMorgan Government Bond Index – Emerging Markets Global Diversified Index (reflects no deduction for fees, expenses or taxes) index_Russell_20002500_Linked_Index_reflects_no_deduction_for_fees_expenses_or_taxes_Open Russell 2000/2500 Linked Index (reflects no deduction for fees, expenses or taxes) (Open) index_SP_500_Index_reflects_no_deduction_for_fees_expenses_or_taxes_Institutional_and_Open S&P 500 Index (reflects no deduction for fees, expenses or taxes) (Institutional and Open) index_BofA_Merrill_Lynch_US_Convertible_ex_Mandatory_Index_reflects_no_deduction_for_fees_expenses_or_taxes BofA Merrill Lynch U.S. Convertible ex Mandatory Index (reflects no deduction for fees, expenses or taxes) index_Bank_of_America_Merrill_Lynch_BBB_US_Cash_Pay_NonDistressed_High_Yield_Index_reflects_no_deduction_for_fees_expenses_or_taxes_Open Bank of America Merrill Lynch BB-B US Cash Pay Non-Distressed High Yield Index (reflects no deduction for fees, expenses or taxes) (Open) index_50_FTSE_NAREIT_All_Equity_REITs_Index50_Wells_Fargo_Hybrid_and_Preferred_Securities_REIT_Index_reflects_no_deduction_for_fees_expenses_or_taxes_Open 50% FTSE NAREIT All Equity REITs Index/50% Wells Fargo Hybrid and Preferred Securities REIT Index (reflects no deduction for fees, expenses or taxes) (Open) index_Russell_1000_ValueSP_500_Linked_Index_reflects_no_deduction_for_fees_expenses_or_taxes Russell 1000 Value/S&P 500 Linked Index (reflects no deduction for fees, expenses or taxes) index_MSCI_Emerging_Markets_Index_reflects_no_deduction_for_fees_expenses_or_taxes MSCI Emerging Markets Index (reflects no deduction for fees, expenses or taxes) index_MSCI_World_Index_reflects_no_deduction_for_fees_expenses_or_taxes_Open MSCI World Index (reflects no deduction for fees, expenses or taxes) (Open) Risk/Return: Prospectus: Document Type Document Period End Date Registrant Name Central Index Key Amendment Flag Document Creation Date Document Effective Date Trading Symbol Prospectus Date Lazard US Equity Concentrated Portfolio Open Shares (Lazard US Equity Concentrated Portfolio) Open Shares Institutional Shares (Lazard US Equity Concentrated Portfolio) Institutional Shares R6 Shares (Lazard US Equity Concentrated Portfolio) R6 Shares Redemption Fee (as a % of amount redeemed, on shares owned for 30 days or less) Management Fees Distribution and Service (12b-1) Fees Other Expenses Total Annual Portfolio Operating Expenses Expense Example, with Redemption, 1 Year 1 Year Expense Example, No Redemption, 1 Year 1 Year Expense Example, with Redemption, 3 Years 3 Years Expense Example, No Redemption, 3 Years 3 Years Expense Example, with Redemption, 5 Years 5 Years Expense Example, No Redemption, 5 Years 5 Years Expense Example, with Redemption, 10 Years 10 Years Expense Example, No Redemption, 10 Years 10 Years Annual Return 1990 Annual Return 1991 Annual Return 1992 Annual Return 1993 Annual Return 1994 Annual Return 1995 Annual Return 1996 Annual Return 1997 Annual Return 1998 Annual Return 1999 Annual Return 2000 Annual Return 2001 Annual Return 2002 Annual Return 2003 Annual Return 2004 Annual Return 2005 Annual Return 2006 Annual Return 2007 Annual Return 2008 Annual Return 2009 Annual Return 2010 Annual Return 2011 Annual Return 2012 Annual Return 2013 Annual Return 2014 Annual Return 2015 Annual Return 2016 Annual Return 2017 Annual Return 2018 Annual Return 2019 Annual Return 2020 1 Year 1 Year 5 Years 5 Years 10 Years 10 Years Since Inception Life of Portfolio Inception Date Inception Date After Taxes on Distributions After Taxes on Distributions After Taxes on Distributions and Sales After Taxes on Distributions and Sales Lazard US Strategic Equity Portfolio Open Shares (Lazard US Strategic Equity Portfolio) Open Shares Institutional Shares (Lazard US Strategic Equity Portfolio) Institutional Shares R6 Shares (Lazard US Strategic Equity Portfolio) R6 Shares Fee Waiver and Expense Reimbursement Total Annual Portfolio Operating Expenses After Fee Waiver and Expense Reimbursement Lazard US Mid Cap Equity Portfolio Open Shares (Lazard US Mid Cap Equity Portfolio) Open Shares Institutional Shares (Lazard US Mid Cap Equity Portfolio) Institutional Shares R6 Shares (Lazard US Mid Cap Equity Portfolio) R6 Shares Lazard US Small-Mid Cap Equity Portfolio Open Shares (Lazard US Small-Mid Cap Equity Portfolio) Open Shares Institutional Shares (Lazard US Small-Mid Cap Equity Portfolio) Institutional Shares R6 Shares (Lazard US Small-Mid Cap Equity Portfolio) R6 Shares Lazard International Equity Portfolio Open Shares (Lazard International Equity Portfolio) Open Shares Institutional Shares (Lazard International Equity Portfolio) Institutional Shares R6 Shares (Lazard International Equity Portfolio) R6 Shares Lazard International Equity Select Portfolio Open Shares (Lazard International Equity Select Portfolio) Open Shares Institutional Shares (Lazard International Equity Select Portfolio) Institutional Shares R6 Shares (Lazard International Equity Select Portfolio) R6 Shares Lazard International Equity Advantage Portfolio Institutional Shares (Lazard International Equity Advantage Portfolio) Institutional Shares Open Shares (Lazard International Equity Advantage Portfolio) Open Shares R6 Shares (Lazard International Equity Advantage Portfolio) R6 Shares Lazard International Equity Concentrated Portfolio Institutional Shares (Lazard International Equity Concentrated Portfolio) Institutional Shares Open Shares (Lazard International Equity Concentrated Portfolio) Open Shares R6 Shares (Lazard International Equity Concentrated Portfolio) R6 Shares Lazard International Strategic Equity Portfolio Open Shares (Lazard International Strategic Equity Portfolio) Open Shares Institutional Shares (Lazard International Strategic Equity Portfolio) Institutional Shares R6 Shares (Lazard International Strategic Equity Portfolio) R6 Shares