Fair Value Of Financial Instruments (Estimated Fair Values Of Financial Instruments Not Measured At Fair Value On A Recurring Basis) (Details) - USD ($) $ in Thousands		Dec. 31, 2023	Dec. 31, 2022
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities purchased under agreements to resell		$ 349,849	$ 348,162
Held-to-maturity securities	[1]	5,852,176	5,738,418
Securities sold under agreements to repurchase		417,644	212,011
Fair Value, Measurements, Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash		3,357,095	2,198,335
Cash segregated for regulatory purposes		162,048	29,017
Securities purchased under agreements to resell		349,849	348,162
Held-to-maturity securities		5,852,176	5,738,418
Bank loans		18,259,923	19,752,043
Loans held for sale		423,999	156,912
Securities sold under agreements to repurchase		417,644	212,011
Bank deposits		25,326,174	24,274,224
Senior notes		1,041,217	1,016,755
Debentures to Stifel Financial Capital Trusts		55,507	53,385
Fair Value, Measurements, Nonrecurring [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash		3,357,095	2,198,335
Cash segregated for regulatory purposes		162,048	29,017
Securities purchased under agreements to resell		0	218,515
Held-to-maturity securities		0
Bank loans		0
Loans held for sale		0
Securities sold under agreements to repurchase		0
Bank deposits		0
Senior notes		1,041,217	1,016,755
Debentures to Stifel Financial Capital Trusts		0
Fair Value, Measurements, Nonrecurring [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash		0
Cash segregated for regulatory purposes		0
Securities purchased under agreements to resell		349,849	129,647
Held-to-maturity securities		5,758,130	5,624,042
Bank loans		18,259,923	19,752,043
Loans held for sale		423,999	156,912
Securities sold under agreements to repurchase		417,644	212,011
Bank deposits		25,326,174	24,274,224
Senior notes		0
Debentures to Stifel Financial Capital Trusts		0
Fair Value, Measurements, Nonrecurring [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash		0
Cash segregated for regulatory purposes		0
Securities purchased under agreements to resell		0
Held-to-maturity securities		94,046	114,376
Bank loans		0
Loans held for sale		0
Securities sold under agreements to repurchase		0
Bank deposits		0
Senior notes		0
Debentures to Stifel Financial Capital Trusts		$ 55,507	$ 53,385

[1] Held-to-maturity securities are carried in the consolidated statements of financial condition at amortized cost, and the changes in the value of these securities, other than impairment charges, are not reported on the consolidated financial statements.