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	Sep. 30, 2013	Dec. 31, 2012
Cash and cash equivalents	$ 138,833	$ 72,596
Securities purchased under agreements to resell	168,182	158,695
Held-to-maturity securities, Estimated fair value	1,732,534	715,274	[1]
Investments	233,778	236,434
Securities sold under agreements to repurchase	255,451	140,346
Bank deposits	4,228,405	3,346,133
Senior notes	357,111	383,992
Level 1 [Member]
Cash and cash equivalents	138,833	72,596
Fair Value, Measurements, Nonrecurring [Member]
Cash and cash equivalents	510,411	331,345
Restricted cash	4,419	4,414
Cash segregated for regulatory purposes	33	128,031
Securities purchased under agreements to resell	168,182	158,695
Held-to-maturity securities, Estimated fair value	1,732,534	715,274
Loans held for sale	75,440	214,531
Bank loans	1,076,079	834,188
Securities sold under agreements to repurchase	255,451	140,346
Bank deposits	3,659,589	3,368,643
Senior notes	335,986	338,475
Non-Recourse Debt	32,541	58,992
Debentures to Stifel Financial Capital Trusts	74,313	66,545
Liabilities subordinated to the claims of general creditors	3,097	5,204
Fair Value, Measurements, Nonrecurring [Member] | Level 1 [Member]
Cash and cash equivalents	510,411	331,345
Restricted cash	4,419	4,414
Cash segregated for regulatory purposes	33	128,031
Securities purchased under agreements to resell	144,171	154,688
Securities sold under agreements to repurchase	4,131	140,346
Senior notes	335,986	338,475
Fair Value, Measurements, Nonrecurring [Member] | Level 2 [Member]
Securities purchased under agreements to resell	24,011	4,007
Held-to-maturity securities, Estimated fair value	1,500,738	487,775
Loans held for sale	75,440	214,531
Bank loans	1,076,079	834,188
Securities sold under agreements to repurchase	251,320
Bank deposits	3,659,589	3,368,643
Non-Recourse Debt	32,541	58,992
Fair Value, Measurements, Nonrecurring [Member] | Level 3 [Member]
Held-to-maturity securities, Estimated fair value	231,796	227,499
Debentures to Stifel Financial Capital Trusts	74,313	66,545
Liabilities subordinated to the claims of general creditors	$ 3,097	$ 5,204

[1] Held-to-maturity securities are carried at historical cost or at fair value at the time of transfer from the available-for-sale to held-to-maturity category, adjusted for amortization of premiums and accretion of discounts and credit-related other-than-temporary impairment.