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, 2021		Dec. 31, 2020	Dec. 31, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash			$ 2,245,082
Cash segregated for regulatory purposes			172,932
Securities purchased under agreements to resell	$ 579,866		217,930
Held-to-maturity securities	5,343,481	[1]	4,107,960
Bank loans			11,088,058
Loans held for sale			551,248
Securities sold under agreements to repurchase	385,528		190,955
Bank deposits			17,192,722
Senior notes			1,265,669
Debentures to Stifel Financial Capital Trusts			41,071
Fair Value, Measurements, Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash	1,960,322
Cash segregated for regulatory purposes	186,331
Securities purchased under agreements to resell	579,866
Held-to-maturity securities	5,343,481
Bank loans	16,704,912
Loans held for sale	207,715
Securities sold under agreements to repurchase	385,528
Bank deposits	22,998,842
Senior notes	1,218,344
Debentures to Stifel Financial Capital Trusts	46,340
Fair Value, Measurements, Nonrecurring [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash	1,960,322			$ 2,245,082
Cash segregated for regulatory purposes	186,331			172,932
Securities purchased under agreements to resell	371,797			164,094
Securities sold under agreements to repurchase	10,000
Senior notes	1,218,344			1,265,669
Fair Value, Measurements, Nonrecurring [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities purchased under agreements to resell	208,069			53,836
Held-to-maturity securities	5,205,085			3,943,944
Bank loans	16,704,912			11,088,058
Loans held for sale	207,715			551,248
Securities sold under agreements to repurchase	375,528			190,955
Bank deposits	22,998,842			$ 17,192,722
Fair Value, Measurements, Nonrecurring [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity securities	138,396		164,016
Debentures to Stifel Financial Capital Trusts	$ 46,340		$ 41,071

[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.