Consolidated Statements of Financial Condition (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Debt Securities, Available-for-sale, Amortized Cost	$ 802,652	$ 706,826
Accounts Receivable, Allowances	4,683	2,704	$ 5,372
Furniture, Equipment and Leasehold Improvements, Accumulated Depreciation and Amortization	$ 187,077	165,857
Intangible Assets, Accumulated Amortization		$ 3,294
Treasury Stock at Cost, shares	41,339,113	36,900,858
Class A [Member]
Common Stock, Par Value (in dollars per share)	$ 0.01	$ 0.01
Common Stock, Shares Authorized	1,000,000,000	1,000,000,000
Common Stock, Shares, Issued	79,686,375	74,804,288
Common Stock, Shares, Outstanding	38,347,262	37,903,430
Class B [Member]
Common Stock, Par Value (in dollars per share)	$ 0.01	$ 0.01
Common Stock, Shares Authorized	1,000,000	1,000,000
Common Stock, Shares, Issued	50	53
Common Stock, Shares, Outstanding	50	53