Cover Page - USD ($)	12 Months Ended
	Dec. 31, 2020	Jan. 31, 2021	Jun. 30, 2020
Entity Information [Line Items]
Document Type	10-K
Document Annual Report	true
Document Transition Report	false
Document Period End Date	Dec. 31, 2020
Entity File Number	000-15637
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	FY
Entity Registrant Name	SVB FINANCIAL GROUP
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	91-1962278
Entity Central Index Key	0000719739
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Emerging Growth Company	false
Entity Small Business	false
Entity Shell Company	false
Amendment Flag	false
Entity Common Stock, Shares Outstanding		51,949,900
Entity Address, Address Line One	3003 Tasman Drive
Entity Address, City or Town	Santa Clara
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	95054-1191
City Area Code	408
Local Phone Number	654-7400
Entity Public Float			$ 10,704,636,319
ICFR Auditor Attestation Flag	true
Documents Incorporated by Reference	Definitive proxy statement for the Company's 2021 Annual Meeting of Stockholders to be filed within 120 days of the end of the fiscal year ended December 31, 2020
Common Stock
Entity Information [Line Items]
Title of 12(b) Security	Common stock, par value $0.001 per share
Trading Symbol	SIVB
Security Exchange Name	NASDAQ
Preferred Stock, Series A
Entity Information [Line Items]
Title of 12(b) Security	Depositary shares, each representing a 1/40th ownership interest in a share of 5.250% Fixed-Rate Non-Cumulative Perpetual Preferred Stock, Series A
Trading Symbol	SIVBP
Security Exchange Name	NASDAQ