Fair Value Of Financial Instruments (Estimated Fair Values Of Financial Instruments Not Measured At Fair Value On A Recurring Basis) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2012		Dec. 31, 2011
Cash and cash equivalents	$ 48,751		$ 14,156
Securities purchased under agreements to resell	103,958		75,455
Investments	244,106		239,208
Securities sold under agreements to repurchase	142,119		80,176
Bank deposits	2,357,912		2,071,738
Senior notes	175,000
Level 1 [Member]
Cash and cash equivalents	48,751		14,156
Carrying Value [Member]
Cash and cash equivalents	226,458		167,671
Restricted cash	6,584		6,883
Cash segregated for regulatory purposes	26		26
Securities purchased under agreements to resell	103,958		75,455
Held-to-maturity securities	327,447		190,484
Loans held for sale	141,136		131,754
Bank loans	657,193		632,140
Investments	244,106		239,208
Securities sold under agreements to repurchase	142,119		80,176
Bank deposits	2,357,912		2,071,738
Debentures to Stifel Financial Capital Trusts	82,500		82,500
Liabilities subordinated to the claims of general creditors	5,318		6,957
Estimated Fair Value [Member]
Cash and cash equivalents	226,458		167,671
Restricted cash	6,584		6,883
Cash segregated for regulatory purposes	26		26
Securities purchased under agreements to resell	103,958		75,455
Held-to-maturity securities	329,833		189,071
Loans held for sale	141,136		131,754
Bank loans	665,773		639,341
Investments	244,106		239,208
Securities sold under agreements to repurchase	142,119		80,176
Bank deposits	2,326,411		2,067,324
Debentures to Stifel Financial Capital Trusts	69,206		67,594
Liabilities subordinated to the claims of general creditors	5,079		6,671
Estimated Fair Value [Member] | Level 1 [Member]
Cash and cash equivalents	177,707	[1]
Restricted cash	6,584	[1]
Cash segregated for regulatory purposes	26	[1]
Securities purchased under agreements to resell	103,958	[1]
Held-to-maturity securities	14,707	[1]
Securities sold under agreements to repurchase	35,809	[1]
Senior notes	189,108	[1]
Fair Value, Measurements, Recurring [Member]
Cash and cash equivalents	177,707	[1]
Restricted cash	6,584	[1]
Cash segregated for regulatory purposes	26	[1]
Securities purchased under agreements to resell	103,958	[1]
Held-to-maturity securities	329,833	[1]
Loans held for sale	141,136	[1]
Bank loans	665,773	[1]
Investments	28,000	[1]
Securities sold under agreements to repurchase	142,119	[1]
Bank deposits	2,326,411	[1]
Senior notes	189,108	[1]
Debentures to Stifel Financial Capital Trusts	69,206	[1]
Liabilities subordinated to the claims of general creditors	5,079	[1]
Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
Held-to-maturity securities	39,537	[1]
Loans held for sale	141,136	[1]
Bank loans	665,773	[1]
Securities sold under agreements to repurchase	106,310	[1]
Bank deposits	2,326,411	[1]
Fair Value, Measurements, Recurring [Member] | Level 3 [Member]
Held-to-maturity securities	275,589	[1]
Investments	28,000	[1]
Debentures to Stifel Financial Capital Trusts	69,206	[1]
Liabilities subordinated to the claims of general creditors	$ 5,079	[1]

[1] We adopted the provisions of Update No. 2011-04 in the first quarter of 2012 on a prospective basis. Accordingly, disclosures for prior periods are not presented.