Interim Consolidated Statements of Stockholders' Equity - USD ($) $ in Millions	Total	Noncumulative Preferred Stock	Preferred Stock	Preferred Stock Noncumulative Preferred Stock	Common Stock	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Total SVBFG Stockholders’ Equity	Total SVBFG Stockholders’ Equity Noncumulative Preferred Stock	Noncontrolling Interests
Balance (in shares) at Dec. 31, 2020					51,888,463
Balance, beginning of period, net of tax at Dec. 31, 2020	$ 8,433		$ 340		$ 0	$ 1,585	$ 5,672	$ 623	$ 8,220		$ 213
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock issued under employee benefit plans, net of restricted stock cancellations (in shares)					374,039
Common stock issued under employee benefit plans, net of restricted stock cancellations	(1)				$ 0	(1)			(1)
Issuance of stock (in shares)					4,527,000
Issuance of stock	2,363	$ 1,724		$ 1,724	$ 0	2,363			2,363	$ 1,724
Issuance of common stock for the acquisition of Boston Private (in shares)					1,887,981
Issuance of common stock for the acquisition of Boston Private	1,060					1,060			1,060
Net income	1,665						1,439		1,439		226
Capital calls and distributions, net	(70)										(70)
Other comprehensive income (loss), net of tax	(558)							(558)	(558)
Share-based compensation, net	93					93			93
Dividends on preferred stock	(40)						(40)		(40)
Balance (in shares) at Sep. 30, 2021					58,677,483
Balance, end of period, net of tax at Sep. 30, 2021	14,669		2,064		$ 0	5,100	7,071	65	14,300		369
Balance (in shares) at Jun. 30, 2021					54,530,307
Balance, beginning of period, net of tax at Jun. 30, 2021	11,967		2,064		$ 0	2,755	6,706	142	11,667		300
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock issued under employee benefit plans, net of restricted stock cancellations (in shares)					32,195
Common stock issued under employee benefit plans, net of restricted stock cancellations	2					2			2
Issuance of stock (in shares)					2,227,000
Issuance of stock	1,245				$ 0	1,245			1,245
Issuance of common stock for the acquisition of Boston Private (in shares)					1,887,981
Issuance of common stock for the acquisition of Boston Private	1,060				$ 0	1,060			1,060
Net income	475						387		387		88
Capital calls and distributions, net	(19)										(19)
Other comprehensive income (loss), net of tax	(77)							(77)	(77)
Share-based compensation, net	38					38			38
Dividends on preferred stock	(22)						(22)		(22)
Balance (in shares) at Sep. 30, 2021					58,677,483
Balance, end of period, net of tax at Sep. 30, 2021	14,669		2,064		$ 0	5,100	7,071	65	14,300		369
Balance (in shares) at Dec. 31, 2021					58,748,469
Balance, beginning of period, net of tax at Dec. 31, 2021	16,609		3,646		$ 0	5,157	7,442	(9)	16,236		373
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock issued under employee benefit plans, net of restricted stock cancellations (in shares)					355,655
Common stock issued under employee benefit plans, net of restricted stock cancellations	(31)				$ 0	(31)			(31)
Net income	1,304						1,357		1,357		(53)
Capital calls and distributions, net	(19)										(19)
Other comprehensive income (loss), net of tax	(2,076)							(2,076)	(2,076)
Share-based compensation, net	146					146			146
Dividends on preferred stock	(123)						(123)		(123)
Balance (in shares) at Sep. 30, 2022					59,104,124
Balance, end of period, net of tax at Sep. 30, 2022	15,810		3,646		$ 0	5,272	8,676	(2,085)	15,509		301
Balance (in shares) at Jun. 30, 2022					59,081,326
Balance, beginning of period, net of tax at Jun. 30, 2022	16,276		3,646		$ 0	5,223	8,247	(1,198)	15,918		358
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock issued under employee benefit plans, net of restricted stock cancellations (in shares)					22,798
Common stock issued under employee benefit plans, net of restricted stock cancellations	(2)					(2)			(2)
Net income	418						469		469		(51)
Capital calls and distributions, net	(6)										(6)
Other comprehensive income (loss), net of tax	(887)							(887)	(887)
Share-based compensation, net	51					51			51
Dividends on preferred stock	(40)						(40)		(40)
Balance (in shares) at Sep. 30, 2022					59,104,124
Balance, end of period, net of tax at Sep. 30, 2022	$ 15,810		$ 3,646		$ 0	$ 5,272	$ 8,676	$ (2,085)	$ 15,509		$ 301