Schedule I - Condensed Statements of Financial Condition (Parent Company Only) (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
ASSETS
Cash and cash equivalents	$ 1,465,022	$ 1,389,876	$ 1,231,593
Investments in subsidiaries, equity method	16,250
Other assets	373,081	307,332
Total Assets	7,147,181	5,971,861	5,639,581
Liabilities:
Other liabilities	626,203	524,538
Total Liabilities	5,494,217	4,972,428
Commitments and contingencies
Common stock:
Class A, par value $.01 per share (500,000,000 shares authorized; 112,766,091 shares issued at December 31, 2021 and 2020, including shares held by subsidiaries as indicated below)	1,128	1,128
Additional paid-in-capital	144,729	135,439
Retained earnings	1,560,636	1,295,386
Accumulated other comprehensive loss, net of tax	(223,847)	(238,368)
Stockholders' equity subtotal before common stock held by subsidiaries and Noncontrolling interests, total	1,482,646	1,193,585
Class A common stock held by subsidiaries, at cost (12,046,140 and 7,728,387 shares at December 31, 2021 and 2020, respectively)	(507,426)	(281,813)
Total Lazard Ltd Stockholders’ Equity	975,220	911,772
Total Liabilities, Redeemable Noncontrolling Interests and Stockholders’ Equity	7,147,181	5,971,861
Series A Preferred Stock [Member]
Preferred stock:
Preferred stock
Series B Preferred Stock [Member]
Preferred stock:
Preferred stock
Parent Company [Member]
ASSETS
Cash and cash equivalents	1,208	453	$ 2,734	$ 4,136
Investments in subsidiaries, equity method	(859,162)	(931,614)
Due from subsidiaries	1,843,022	1,850,887
Other assets	8	29
Total Assets	985,076	919,755
Liabilities:
Due to subsidiaries	9,694	7,829
Other liabilities	162	154
Total Liabilities	9,856	7,983
Commitments and contingencies
Common stock:
Class A, par value $.01 per share (500,000,000 shares authorized; 112,766,091 shares issued at December 31, 2021 and 2020, including shares held by subsidiaries as indicated below)	1,128	1,128
Additional paid-in-capital	144,729	135,439
Retained earnings	1,560,636	1,295,386
Accumulated other comprehensive loss, net of tax	(223,847)	(238,368)
Stockholders' equity subtotal before common stock held by subsidiaries and Noncontrolling interests, total	1,482,646	1,193,585
Class A common stock held by subsidiaries, at cost (12,046,140 and 7,728,387 shares at December 31, 2021 and 2020, respectively)	(507,426)	(281,813)
Total Lazard Ltd Stockholders’ Equity	975,220	911,772
Total Liabilities, Redeemable Noncontrolling Interests and Stockholders’ Equity	985,076	919,755
Parent Company [Member] | Series A Preferred Stock [Member]
Preferred stock:
Preferred stock
Parent Company [Member] | Series B Preferred Stock [Member]
Preferred stock:
Preferred stock