Senior Debt - Senior Debt (Parenthetical) (Detail)	3 Months Ended
Mar. 31, 2022
Lazard Group 3.75% Senior Notes [Member]
Debt Instrument [Line Items]
Senior notes interest rate	3.75%
Senior debt maturity date	Feb. 13, 2025
Effective interest rates of senior notes	3.87%
Lazard Group 3.625% Senior Notes [Member]
Debt Instrument [Line Items]
Senior notes interest rate	3.625%
Senior debt maturity date	Mar. 01, 2027
Effective interest rates of senior notes	3.76%
Lazard Group 4.50% Senior Notes [Member]
Debt Instrument [Line Items]
Senior notes interest rate	4.50%
Senior debt maturity date	Sep. 19, 2028
Effective interest rates of senior notes	4.67%
Lazard Group 4.375% Senior Notes [Member]
Debt Instrument [Line Items]
Senior notes interest rate	4.375%
Senior debt maturity date	Mar. 11, 2029
Effective interest rates of senior notes	4.53%

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Date when the debt instrument is scheduled to be fully repaid, in YYYY-MM-DD format.

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