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, 2012	Dec. 31, 2011
Cash and cash equivalents	$ 26,675	$ 14,156
Securities purchased under agreements to resell	141,964	75,455
Investments	242,674	239,208
Securities sold under agreements to repurchase	78,437	80,176
Bank deposits	2,923,671	2,071,738
Senior notes	175,000
Level 1 [Member]
Cash and cash equivalents	26,675	14,156
Fair Value, Measurements, Nonrecurring [Member]
Cash and cash equivalents	166,658
Restricted cash	6,589
Cash segregated for regulatory purposes	28
Securities purchased under agreements to resell	141,964
Held-to-maturity securities	664,593
Loans held for sale	209,358
Bank loans	765,467
Investments
Securities sold under agreements to repurchase	78,437
Bank deposits	2,924,394
Senior notes	185,034
Debentures to Stifel Financial Capital Trusts	53,517
Liabilities subordinated to the claims of general creditors	5,162
Fair Value, Measurements, Nonrecurring [Member] \| Level 1 [Member]
Cash and cash equivalents	166,658
Restricted cash	6,589
Cash segregated for regulatory purposes	28
Securities purchased under agreements to resell	141,964
Held-to-maturity securities	14,796
Loans held for sale
Bank loans
Investments
Securities sold under agreements to repurchase	32,841
Bank deposits
Senior notes	185,034
Debentures to Stifel Financial Capital Trusts
Liabilities subordinated to the claims of general creditors
Fair Value, Measurements, Nonrecurring [Member] \| Level 2 [Member]
Cash and cash equivalents
Restricted cash
Cash segregated for regulatory purposes
Securities purchased under agreements to resell
Held-to-maturity securities	39,672
Loans held for sale	209,358
Bank loans	765,467
Investments
Securities sold under agreements to repurchase	45,596
Bank deposits	2,924,394
Senior notes
Debentures to Stifel Financial Capital Trusts
Liabilities subordinated to the claims of general creditors
Fair Value, Measurements, Nonrecurring [Member] \| Level 3 [Member]
Cash and cash equivalents
Restricted cash
Cash segregated for regulatory purposes
Securities purchased under agreements to resell
Held-to-maturity securities	610,125
Loans held for sale
Bank loans
Investments
Securities sold under agreements to repurchase
Bank deposits
Senior notes
Debentures to Stifel Financial Capital Trusts	53,517
Liabilities subordinated to the claims of general creditors	$ 5,162

Cash Segregated for Regulatory Purposes, Fair Value Disclosure

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Restricted Cash, Fair Value Disclosure

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- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Company may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months.

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The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others.

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Amount of subordinated debt obligations (also known as subordinated loan, subordinated bond, subordinated debenture or junior debt) which has a priority ranking after other debts in a dissolution, measured at fair value.

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Sum of the carrying amounts as of the balance sheet date of all investments.

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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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The carrying value of funds outstanding loaned in the form of security resale agreements if the agreement requires the purchaser to resell the identical security purchased or a security that meets the definition of "substantially the same." Also includes purchases of participations in pools of securities that are subject to a resale agreement.

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The carrying value as of the balance sheet date of securities that an institution sells and agrees to repurchase (the identical or substantially the same securities) as a seller-borrower at a specified date for a specified price, also known as a repurchase agreement, or repo. Most repos involve obligations of the federal government or its agencies, but other financial instruments, such as commercial paper, banker's acceptances, and negotiable certificates of deposit, are sometimes used in repos.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of uncollateralized debt obligations (with maturities initially due after one year or beyond the operating cycle if longer).

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