Fair Value Of Financial Instruments (Schedule Of Fair Value Of Financial Instruments) (Details) - USD ($) $ in Thousands		Dec. 31, 2020	Dec. 31, 2019
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Securities purchased under agreements to resell	[1]	$ 217,930	$ 385,008
Financial instruments owned		694,028	972,932
Available-for-sale securities		2,230,297	3,254,737
Held-to-maturity securities		4,107,960	2,827,883
Derivative contracts	[2]		1,086
Securities sold under agreements to repurchase	[3]	190,955	391,634
Financial instruments sold, but not yet purchased, at fair value		437,978	662,852
Federal Home Loan Bank advances		0
Senior notes		1,112,409	1,017,010
Carrying Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents		2,279,274	1,142,596
Cash segregated for regulatory purposes		172,932	131,374
Securities purchased under agreements to resell		217,930	385,008
Financial instruments owned		694,028	972,932
Available-for-sale securities		2,230,297	3,254,737
Held-to-maturity securities		4,117,384	2,856,219
Bank loans		11,006,760	9,624,042
Loans held for sale		551,248	389,693
Investments		113,862	79,972
Derivative contracts	[2]		1,086
Securities sold under agreements to repurchase		190,955	391,634
Bank deposits		17,396,497	15,332,581
Financial instruments sold, but not yet purchased, at fair value		437,978	662,852
Federal Home Loan Bank advances			250,000
Senior notes		1,112,409	1,017,010
Debentures to Stifel Financial Capital Trusts		60,000	60,000
Estimated Fair Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents		2,279,274	1,142,596
Cash segregated for regulatory purposes		172,932	131,374
Securities purchased under agreements to resell		217,930	385,008
Financial instruments owned		694,028	972,932
Available-for-sale securities		2,230,297	3,254,737
Held-to-maturity securities		4,107,960	2,827,883
Bank loans		11,088,058	9,801,986
Loans held for sale		551,248	389,693
Investments		113,862	79,972
Derivative contracts	[2]		1,086
Securities sold under agreements to repurchase		190,955	391,634
Bank deposits		17,192,722	14,467,894
Financial instruments sold, but not yet purchased, at fair value		437,978	662,852
Federal Home Loan Bank advances			250,000
Senior notes		1,265,669	1,069,425
Debentures to Stifel Financial Capital Trusts		$ 41,071	$ 45,847

[1] Collateral received includes securities received by our company from the counterparty. These securities are not included on the consolidated statements of financial condition unless there is an event of default. The fair value of securities pledged as collateral was $217.3 million and $385.3 million at December 31, 2020 and 2019, respectively.

[2] Included in other assets in the consolidated statements of financial condition.

[3] Collateral pledged includes the fair value of securities pledged by our company to the counter party. These securities are included on the consolidated statements of financial condition unless we default. Collateral pledged by our company to the counter party includes U.S. government agency securities, U.S. government securities, and corporate fixed income securities with market values of $200.2 million and $407.3 million at December 31, 2020 and 2019, respectively.