Subsequent Events (Details) (KBW [Member], USD $) In Millions, except Per Share data, unless otherwise specified	9 Months Ended
Sep. 30, 2012
Business Acquisition [Line Items]
Date of acquisition agreement	Nov. 05, 2012
Percentage of outstanding shares acquired	100.00%
Price per share	$ 17.50
Per share in cash	$ 10.00
Per share in Stifel common stock	$ 7.50
Estimated purchase price	$ 577.8
Holders Of Restricted KBW Shares [Member]
Business Acquisition [Line Items]
Per share in Stifel common stock	$ 17.50

Business acquisition, share price, cash portion.

No definition available.

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Namespace Prefix:	sf_
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Balance Type:	na
Period Type:	duration

- Definition

Business acquisition, share price, common stock portion.

+ References

No definition available.

+ Details

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Namespace Prefix:	sf_
Data Type:	num:perShareItemType
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Period Type:	duration

- Definition

The total cost of the acquired entity including the cash paid to shareholders of acquired entities, fair value of debt and equity securities issued to shareholders of acquired entities, the fair value of the liabilities assumed, and direct costs of the acquisition.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 51

-Subparagraph d

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Date when the business acquisition agreement was executed, in CCYY-MM-DD format.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of voting equity interests acquired in the business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=7659399&loc=d3e1392-128463

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141R

-Paragraph 68

-Subparagraph c

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

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Balance Type:	na
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- Definition

For an acquired entity, price of a single share of a number of saleable stocks of a company.

+ References

No definition available.

+ Details

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Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant