Consolidated Statements Of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024
Cash Flows From Operating Activities:
Net income	$ 52,992	$ 163,575
Adjustments to reconcile net income to net cash used in operating activities:
Depreciation and amortization	15,009	15,665
Amortization of loans and advances to financial advisors and other employees	35,796	37,143
Amortization of premium on investment portfolio	1,727	2,142
Provision for credit losses and allowance for loans and advances to financial advisors and other employees	12,020	5,269
Amortization of intangible assets	5,396	5,842
Deferred income taxes	(29,668)	(2,655)
Stock-based compensation	57,633	56,797
(Gains)/losses on sale of investments	(405)	373
Gain on sale of leased aircraft engines	(3,610)	0
Other, net	1,638	(5,974)
Receivables:
Brokerage clients	(53,407)	(34,495)
Brokers, dealers, and clearing organizations	48,306	(243,727)
Securities purchased under agreements to resell	(113,874)	(101,207)
Financial instruments owned	(250,148)	(312,114)
Loans originated as held for sale	(512,027)	(545,666)
Proceeds from loans held for sale	543,192	444,364
Loans and advances to financial advisors and other employees	(24,060)	(87,795)
Other assets	81,775	(98,281)
Increase/(decrease) in operating liabilities, net of liabilities assumed:
Brokerage clients	5,055	15,781
Brokers, dealers, and clearing organizations	46,889	46,495
Drafts	(39,015)	(10,149)
Financial instruments sold, but not yet purchased	179,217	184,538
Other liabilities and accrued expenses	(271,639)	(145,642)
Net cash used in operating activities	(211,208)	(609,721)
Cash Flows From Investing Activities:
Principal paydowns, maturities, and calls of available-for-sale securities	88,000	45,431
Principal paydowns, maturities, and calls of held-to-maturity securities	615,712	183,460
Sale or maturity of investments	6	4,830
Sale of leased aircraft engines	14,616	0
Decrease in loans held for investment, net	24,231	352,537
Payments for:
Purchase of fixed assets	(16,573)	(9,636)
Purchase of available-for-sale securities	(90,408)	(7,000)
Purchase of held-to-maturity securities	(807,335)	(88,500)
Purchase of investments	(768)	(3,590)
Acquisitions, net of cash received	0	(752)
Net cash (used in)/provided by investing activities	(172,519)	476,780
Cash Flows From Financing Activities:
Payment of contingent consideration	(128)	(708)
Increase in securities sold under agreements to repurchase	104,391	9,015
Increase in bank deposits, net	537,045	219,832
Increase in securities loaned	113,316	88,685
Repayment of short-term debt	(18,177)	0
Tax payments related to shares withheld for stock-based compensation plans	(114,596)	(98,638)
Repurchase of common stock	(93,173)	(60,710)
Cash dividends on preferred stock	(9,320)	(9,320)
Cash dividends paid to common stock and equity-award holders	(62,850)	(63,065)
Net cash provided by financing activities	456,508	85,091
Effect of exchange rate changes on cash	3,073	(1,644)
Increase/(decrease) in cash, cash equivalents, and cash segregated for regulatory purposes	75,854	(49,494)
Cash, cash equivalents, and cash segregated for regulatory purposes at beginning of period	2,678,203	3,523,849
Cash, cash equivalents, and cash segregated for regulatory purposes at end of period	2,754,057	3,474,355
Supplemental disclosure of cash flow information:
Cash paid for interest	215,510	257,723
Cash paid for income taxes, net of refunds	8,033	114,746
Noncash financing activities:
Unit grants, net of forfeitures	$ 158,245	$ 124,212