Fair Value Of Financial Instruments (Estimated Fair Values Of Financial Instruments Not Measured At Fair Value On A Recurring Basis) (Details) - USD ($) $ in Thousands		Mar. 31, 2023	Dec. 31, 2022
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities purchased under agreements to resell		$ 549,215	$ 348,162
Held-to-maturity securities	[1]	5,779,545	5,738,418
Securities sold under agreements to repurchase		429,726	212,011
Federal Home Loan Bank advances		0
Fair Value, Measurements, Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash		2,763,178	2,198,335
Cash segregated for regulatory purposes		20,551	29,017
Securities purchased under agreements to resell		549,215	348,162
Held-to-maturity securities		5,779,545	5,738,418
Bank loans		19,847,907	19,752,043
Loans held for sale		225,365	156,912
Securities sold under agreements to repurchase		429,726	212,011
Bank deposits		25,611,711	24,274,224
Senior notes		1,027,532	1,016,755
Debentures to Stifel Financial Capital Trusts		52,958	53,385
Fair Value, Measurements, Nonrecurring [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash		2,763,178	2,198,335
Cash segregated for regulatory purposes		20,551	29,017
Securities purchased under agreements to resell		362,868	218,515
Held-to-maturity securities		0
Bank loans		0
Loans held for sale		0
Securities sold under agreements to repurchase		12,825
Bank deposits		0
Senior notes		1,027,532	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		186,347	129,647
Held-to-maturity securities		5,666,895	5,624,042
Bank loans		19,847,907	19,752,043
Loans held for sale		225,365	156,912
Securities sold under agreements to repurchase		416,901	212,011
Bank deposits		25,611,711	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		112,650	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		$ 52,958	$ 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.