Consolidated Statements of Stockholders' Equity - USD ($) $ in Millions	Total	Noncumulative Preferred Stock	Cumulative adjustment for adoption of amendment	Preferred Stock	Preferred Stock Noncumulative Preferred Stock	Common Stock	Additional Paid-in Capital	Retained Earnings	Retained Earnings Cumulative adjustment for adoption of amendment	Accumulated Other Comprehensive Income (Loss)	Total SVBFG Stockholders’ Equity	Total SVBFG Stockholders’ Equity Noncumulative Preferred Stock	Total SVBFG Stockholders’ Equity Cumulative adjustment for adoption of amendment	Noncontrolling Interests
Balance, beginning of period, net of tax at Dec. 31, 2018	$ 5,265			$ 0		$ 0	$ 1,378	$ 3,792		$ (54)	$ 5,116			$ 149
Balance, beginning of period, net of tax (Accounting Standards Update 2017-08) at Dec. 31, 2018			$ (1)						$ (1)				$ (1)
Balance (in shares) at Dec. 31, 2018						52,586,498
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Acquisition of SVB Securities	5													5
Common stock issued under employee benefit plans and ESOP, net of restricted stock cancellations (in shares)						601,319
Common stock issued under employee benefit plans and ESOP, net of restricted stock cancellations	25					$ 0	25				25
Issuance of stock		$ 340			$ 340							$ 340
Net income	1,185							1,137			1,137			48
Capital calls and distributions, net	(51)													(51)
Other comprehensive income, net of tax	139									139	139
Share-based compensation, net	67						67				67
Common stock repurchases (in shares)						(1,532,210)
Common stock repurchases	(352)					$ 0		(352)			(352)
Balance, end of period, net of tax at Dec. 31, 2019	6,622			340		$ 0	1,470	4,576		85	6,471			151
Balance, end of period, net of tax (ASC 326) at Dec. 31, 2019			$ (35)						$ (35)				$ (35)
Balance (in shares) at Dec. 31, 2019						51,655,607
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock issued under employee benefit plans and ESOP, net of restricted stock cancellations (in shares)						477,079
Common stock issued under employee benefit plans and ESOP, net of restricted stock cancellations	31					$ 0	31				31
Net income	1,294							1,208			1,208			86
Capital calls and distributions, net	(24)													(24)
Other comprehensive income, net of tax	538									538	538
Share-based compensation, net	84						84				84
Common stock repurchases (in shares)						(244,223)
Common stock repurchases	(60)					$ 0		(60)			(60)
Dividends on preferred stock	(17)							(17)			(17)
Balance, end of period, net of tax at Dec. 31, 2020	8,433			340		$ 0	1,585	5,672		623	8,220			213
Balance (in shares) at Dec. 31, 2020						51,888,463
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock issued under employee benefit plans and ESOP, net of restricted stock cancellations (in shares)						445,025
Common stock issued under employee benefit plans and ESOP, net of restricted stock cancellations	11					$ 0	11				11
Issuance of stock (in shares)						4,527,000
Issuance of stock	2,363	$ 3,306			$ 3,306	$ 0	2,363				2,363	$ 3,306
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	2,073							1,833			1,833			240
Capital calls and distributions, net	(80)													(80)
Other comprehensive income, net of tax	(632)									(632)	(632)
Share-based compensation, net	138						138				138
Dividends on preferred stock	(63)							(63)			(63)
Balance, end of period, net of tax at Dec. 31, 2021	$ 16,609			$ 3,646		$ 0	$ 5,157	$ 7,442		$ (9)	$ 16,236			$ 373
Balance (in shares) at Dec. 31, 2021						58,748,469