Document and Entity Information - USD ($) $ in Billions	12 Months Ended
	Dec. 31, 2020	Feb. 12, 2021	Jun. 30, 2020
Document Information [Line Items]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2020
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	FY
Entity Registrant Name	STIFEL FINANCIAL CORP
Entity Central Index Key	0000720672
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Tax Identification Number	43-1273600
Entity Address, Address Line One	501 North Broadway
Entity Address, City or Town	St. Louis
Entity Address, State or Province	MO
Entity Address, Postal Zip Code	63102-2188
City Area Code	314
Local Phone Number	342-2000
Entity File Number	001-09305
Entity Incorporation, State or Country Code	DE
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Public Float			$ 3.4
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
ICFR Auditor Attestation Flag	false
Document Annual Report	true
Document Transition Report	false
Documents Incorporated by Reference	Portions of the Proxy Statement for the annual meeting of shareholders, to be filed within 120 days of our fiscal year ended December 31, 2020, are incorporated by reference in Part III hereof.
Common Stock [Member]
Document Information [Line Items]
Trading Symbol	SF
Title of 12(b) Security	Common Stock, $0.15 par value per share
Security Exchange Name	NYSE
Entity Common Stock, Shares Outstanding		104,973,677
Depository Shares, each representing 1/1,000th interest in a share of 6.25% Non-Cumulative Preferred Stock, Series A [Member]
Document Information [Line Items]
Trading Symbol	SF-PA
Title of 12(b) Security	Depository Shares, each representing 1/1,000th interest in a share of 6.25% Non-Cumulative Preferred Stock, Series A
Security Exchange Name	NYSE
Entity Common Stock, Shares Outstanding		6,000
Depository Shares, each representing 1/1,000th interest in a share of 6.25% Non-Cumulative Preferred Stock, Series B [Member]
Document Information [Line Items]
Trading Symbol	SF-PB
Title of 12(b) Security	Depository Shares, each representing 1/1,000th interest in a share of 6.25% Non-Cumulative Preferred Stock, Series B
Security Exchange Name	NYSE
Entity Common Stock, Shares Outstanding		6,400
Depository Shares, each representing 1/1,000th interest in a share of 6.125% Non-Cumulative Preferred Stock, Series C [Member]
Document Information [Line Items]
Trading Symbol	SF-PC
Title of 12(b) Security	Depository Shares, each representing 1/1,000th interest in a share of 6.125% Non-Cumulative Preferred Stock, Series C
Security Exchange Name	NYSE
Entity Common Stock, Shares Outstanding		9,000
Senior notes 5.20% due 2047 [Member]
Document Information [Line Items]
Trading Symbol	SFB
Title of 12(b) Security	5.20% Senior Notes due 2047
Security Exchange Name	NYSE
Entity Common Stock, Shares Outstanding		225,000,000