Senior Debt - Senior Debt (Detail) - USD ($)	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
Senior Debt, Outstanding Principal	$ 1,700,000,000	$ 1,700,000,000
Senior Debt, Outstanding Unamortized Debt Costs	12,286,000	14,773,000
Senior Debt, Outstanding Carrying Value	1,687,714,000	$ 1,685,227,000
Lazard Group 3.75% Senior Notes [Member]
Debt Instrument [Line Items]
Senior Debt, Initial Principal Amount	$ 400,000,000
Senior Debt, Maturity Date	Feb. 13, 2025	Feb. 13, 2025
Senior Debt, Annual Interest Rate	3.75%
Senior Debt, Outstanding Principal	$ 400,000,000	$ 400,000,000
Senior Debt, Outstanding Unamortized Debt Costs	1,003,000	1,476,000
Senior Debt, Outstanding Carrying Value	398,997,000	$ 398,524,000
Lazard Group 3.625% Senior Notes [Member]
Debt Instrument [Line Items]
Senior Debt, Initial Principal Amount	$ 300,000,000
Senior Debt, Maturity Date	Mar. 01, 2027	Mar. 01, 2027
Senior Debt, Annual Interest Rate	3.625%
Senior Debt, Outstanding Principal	$ 300,000,000	$ 300,000,000
Senior Debt, Outstanding Unamortized Debt Costs	1,625,000	2,015,000
Senior Debt, Outstanding Carrying Value	298,375,000	$ 297,985,000
Lazard Group 4.50% Senior Notes [Member]
Debt Instrument [Line Items]
Senior Debt, Initial Principal Amount	$ 500,000,000
Senior Debt, Maturity Date	Sep. 19, 2028	Sep. 19, 2028
Senior Debt, Annual Interest Rate	4.50%
Senior Debt, Outstanding Principal	$ 500,000,000	$ 500,000,000
Senior Debt, Outstanding Unamortized Debt Costs	4,864,000	5,716,000
Senior Debt, Outstanding Carrying Value	495,136,000	$ 494,284,000
Lazard Group 4.375% Senior Notes [Member]
Debt Instrument [Line Items]
Senior Debt, Initial Principal Amount	$ 500,000,000
Senior Debt, Maturity Date	Mar. 11, 2029	Mar. 11, 2029
Senior Debt, Annual Interest Rate	4.375%
Senior Debt, Outstanding Principal	$ 500,000,000	$ 500,000,000
Senior Debt, Outstanding Unamortized Debt Costs	4,794,000	5,566,000
Senior Debt, Outstanding Carrying Value	$ 495,206,000	$ 494,434,000

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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- Definition

Face (par) amount of debt instrument at time of issuance.

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- Definition

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

+ References

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No definition available.

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- Definition

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

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- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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- Definition

Amount, excluding unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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