Consolidated Statements of Stockholders' Equity - USD ($)	Total	Preferred Stock	Common Stock	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Total SVBFG Stockholders’ Equity	Noncontrolling Interests
Balance (in shares) at Dec. 31, 2016			52,254,074
Balance, beginning of period, net of tax at Dec. 31, 2016	$ 3,777,037,000	$ 0	$ 52,000	$ 1,242,741,000	$ 2,376,331,000	$ 23,430,000	$ 3,642,554,000	$ 134,483,000
Common stock issued under employee benefit plans, net of restricted stock cancellations (in shares)			570,276
Common stock issued under employee benefit plans, net of restricted stock cancellations	24,909,000		$ 1,000	24,908,000			24,909,000
Common stock issued under ESOP (in shares)			10,838
Common stock issued under ESOP	2,094,000			2,094,000			2,094,000
Net income	519,178,000				490,506,000		490,506,000	28,672,000
Capital calls and distributions, net	(23,535,000)							(23,535,000)
Net change in unrealized gains and losses on AFS securities, net of tax	(24,788,000)					(24,788,000)	(24,788,000)
Amortization of unrealized gains on securities transferred from AFS to HTM, net of tax	(3,882,000)					(3,882,000)	(3,882,000)
Foreign currency translation adjustments, net of tax	3,768,000					3,768,000	3,768,000
Share-based compensation, net	44,634,000			44,634,000			44,634,000
Reclassification of stranded tax effect for ASU 2018-02	0
Balance (in shares) at Dec. 31, 2017			52,835,188
Balance, end of period, net of tax at Dec. 31, 2017	4,319,415,000	0	$ 53,000	1,314,377,000	2,866,837,000	(1,472,000)	4,179,795,000	139,620,000
Common stock issued under employee benefit plans, net of restricted stock cancellations (in shares)			456,845
Common stock issued under employee benefit plans, net of restricted stock cancellations	15,810,000		$ 1,000	15,809,000			15,810,000
Common stock issued under ESOP (in shares)			9,672
Common stock issued under ESOP	2,577,000			2,577,000			2,577,000
Net income	1,011,348,000				973,840,000		973,840,000	37,508,000
Capital calls and distributions, net	(28,494,000)							(28,494,000)
Net change in unrealized gains and losses on AFS securities, net of tax	(15,498,000)					(15,498,000)	(15,498,000)
Amortization of unrealized gains on securities transferred from AFS to HTM, net of tax	(3,330,000)					(3,330,000)	(3,330,000)
Foreign currency translation adjustments, net of tax	(4,330,000)					(4,330,000)	(4,330,000)
Share-based compensation, net	45,675,000			45,675,000			45,675,000
Reclassification of stranded tax effect for ASU 2018-02	319,000
Reclassification of stranded tax effect for ASU 2018-02 | Accounting Standards Update 2018-02					319,000	(319,000)
Common stock repurchases (in shares)			(715,207)
Common stock repurchases	(147,123,000)		$ (1,000)		(147,122,000)		(147,123,000)
Balance (in shares) at Dec. 31, 2018			52,586,498
Balance, end of period, net of tax at Dec. 31, 2018	5,264,843,000	0	$ 53,000	1,378,438,000	3,791,838,000	(54,120,000)	5,116,209,000	148,634,000
Common stock issued under employee benefit plans, net of restricted stock cancellations (in shares)			586,877
Common stock issued under employee benefit plans, net of restricted stock cancellations	21,312,000		$ 0	21,312,000			21,312,000
Common stock issued under ESOP (in shares)			14,442
Common stock issued under ESOP	3,506,000			3,506,000			3,506,000
Net income	1,184,717,000				1,136,856,000		1,136,856,000	47,861,000
Capital calls and distributions, net	(50,978,000)							(50,978,000)
Net change in unrealized gains and losses on AFS securities, net of tax	139,934,000					139,934,000	139,934,000
Amortization of unrealized gains on securities transferred from AFS to HTM, net of tax	(1,558,000)					(1,558,000)	(1,558,000)
Foreign currency translation adjustments, net of tax	2,319,000					2,319,000	2,319,000
Share-based compensation, net	66,815,000			66,815,000			66,815,000
Reclassification of stranded tax effect for ASU 2018-02	0
Common stock repurchases (in shares)			(1,532,210)
Common stock repurchases	(352,511,000)		$ (1,000)		(352,510,000)		(352,511,000)
Acquisition of SVB Leerink	5,256,000							5,256,000
Issuance of Series A Preferred Stock	340,138,000	340,138,000					340,138,000
Net change in unrealized gains and losses on cash flow hedges, net of tax	(2,130,000)					(2,130,000)	(2,130,000)
Balance (in shares) at Dec. 31, 2019			51,655,607
Balance, end of period, net of tax at Dec. 31, 2019	$ 6,621,080,000	$ 340,138,000	$ 52,000	$ 1,470,071,000	$ 4,575,601,000	$ 84,445,000	$ 6,470,307,000	$ 150,773,000