Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2021	Aug. 02, 2021
Document Information [Line Items]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jun. 30, 2021
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q2
Entity Registrant Name	STIFEL FINANCIAL CORP
Entity Central Index Key	0000720672
Current Fiscal Year End Date	--12-31
Entity File Number	001-09305
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	43-1273600
Entity Address, Address Line One	501 N. 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
Document Quarterly Report	true
Document Transition Report	false
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
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		104,787,828
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
Depository Shares, each representing 1/1,000th interest in a share of 4.50% Non-Cumulative Preferred Stock, Series D [Member]
Document Information [Line Items]
Trading Symbol	SF-PD
Title of 12(b) Security	Depository Shares, each representing 1/1,000th interest in a share of 4.50% Non-Cumulative Preferred Stock, Series D
Security Exchange Name	NYSE
Entity Common Stock, Shares Outstanding		12,000
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