Interim Consolidated Statements of Stockholders' Equity - USD ($)		Total	Cumulative adjustment for the adoption of amendment	Preferred Stock	Common Stock	Additional Paid-in Capital	Retained Earnings	Retained Earnings Cumulative adjustment for the adoption of amendment	Accumulated Other Comprehensive Income (Loss)	Total SVBFG Stockholders’ Equity	Total SVBFG Stockholders’ Equity Cumulative adjustment for the adoption of amendment	Noncontrolling Interests
Balance (in shares) at Dec. 31, 2018					52,586,498
Balance, beginning 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
Balance, beginning of period, net of tax (Accounting Standards Update 2017-08) at Dec. 31, 2018	[1]		$ (583,000)					$ (583,000)			$ (583,000)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Acquisition of SVB Leerink		5,256,000										5,256,000
Common stock issued under employee benefit plans, net of restricted stock cancellations (in shares)					467,427
Common stock issued under employee benefit plans, net of restricted stock cancellations		7,853,000			$ 0	7,853,000				7,853,000
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		628,183,000					606,719,000			606,719,000		21,464,000
Capital calls and distributions, net		(23,222,000)										(23,222,000)
Net change in unrealized gains and losses on AFS securities, net of tax		122,597,000							122,597,000	122,597,000
Amortization of unrealized holding gains on securities transferred from AFS to HTM, net of tax		(1,005,000)							(1,005,000)	(1,005,000)
Foreign currency translation adjustments, net of tax		(68,000)							(68,000)	(68,000)
Net change in unrealized gains and losses on cash flow hedges, net of tax		13,828,000							13,828,000	13,828,000
Share-based compensation, net		31,768,000				31,768,000				31,768,000
Common stock repurchases (in shares)					(1,506,648)
Common stock repurchases		(346,781,000)			$ (1,000)		(346,780,000)			(346,781,000)
Balance (in shares) at Jun. 30, 2019					51,561,719
Balance, end of period, net of tax at Jun. 30, 2019		5,706,175,000		0	$ 52,000	1,421,565,000	4,051,194,000		81,232,000	5,554,043,000		152,132,000
Balance (in shares) at Mar. 31, 2019					52,322,105
Balance, beginning of period, net of tax at Mar. 31, 2019		5,483,823,000		0	$ 52,000	1,394,130,000	3,963,965,000		(15,374,000)	5,342,773,000		141,050,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock issued under employee benefit plans, net of restricted stock cancellations (in shares)					257,684
Common stock issued under employee benefit plans, net of restricted stock cancellations		10,789,000				10,789,000				10,789,000
Net income		336,571,000					317,987,000			317,987,000		18,584,000
Capital calls and distributions, net		(7,502,000)										(7,502,000)
Net change in unrealized gains and losses on AFS securities, net of tax		86,186,000							86,186,000	86,186,000
Amortization of unrealized holding gains on securities transferred from AFS to HTM, net of tax		(519,000)							(519,000)	(519,000)
Foreign currency translation adjustments, net of tax		(2,092,000)							(2,092,000)	(2,092,000)
Net change in unrealized gains and losses on cash flow hedges, net of tax		13,031,000							13,031,000	13,031,000
Share-based compensation, net		16,646,000				16,646,000				16,646,000
Common stock repurchases (in shares)					(1,018,070)
Common stock repurchases		(230,758,000)					(230,758,000)			(230,758,000)
Balance (in shares) at Jun. 30, 2019					51,561,719
Balance, end of period, net of tax at Jun. 30, 2019		5,706,175,000		0	$ 52,000	1,421,565,000	4,051,194,000		81,232,000	5,554,043,000		152,132,000
Balance (in shares) at Dec. 31, 2019					51,655,607
Balance, beginning of period, net of tax at Dec. 31, 2019		6,621,080,000		340,138	$ 52,000	1,470,071,000	4,575,601,000		84,445,000	6,470,307,000		150,773,000
Balance, beginning of period, net of tax (Accounting Standards Update 2016-13) at Dec. 31, 2019	[1]		$ (35,049,000)					$ (35,049,000)			$ (35,049,000)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock issued under employee benefit plans, net of restricted stock cancellations (in shares)					317,236
Common stock issued under employee benefit plans, net of restricted stock cancellations		10,894,000			$ 0	10,894,000				10,894,000
Common stock issued under ESOP (in shares)					12,094
Common stock issued under ESOP		2,447,000				2,447,000				2,447,000
Net income		381,438,000					369,151,000			369,151,000		12,287,000
Capital calls and distributions, net		(14,120,000)										(14,120,000)
Net change in unrealized gains and losses on AFS securities, net of tax		382,707,000							382,707,000	382,707,000
Amortization of unrealized holding gains on securities transferred from AFS to HTM, net of tax		(499,000)							(499,000)	(499,000)
Foreign currency translation adjustments, net of tax		(6,604,000)							(6,604,000)	(6,604,000)
Net change in unrealized gains and losses on cash flow hedges, net of tax		154,686,000							154,686,000	154,686,000
Share-based compensation, net		39,325,000				39,325,000				39,325,000
Common stock repurchases (in shares)					(244,223)
Common stock repurchases		(60,020,000)			$ 0		(60,020,000)			(60,020,000)
Dividends on preferred stock		(7,963,000)					(7,963,000)			(7,963,000)
Other		(9,000)				(9,000)				(9,000)
Balance (in shares) at Jun. 30, 2020					51,740,714
Balance, end of period, net of tax at Jun. 30, 2020		7,468,313,000		340,138	$ 52,000	1,522,728,000	4,841,720,000		614,735,000	7,319,373,000		148,940,000
Balance (in shares) at Mar. 31, 2020					51,490,342
Balance, beginning of period, net of tax at Mar. 31, 2020		7,183,221,000		340,138	$ 52,000	1,489,240,000	4,612,785,000		592,534,000	7,034,749,000		148,472,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock issued under employee benefit plans, net of restricted stock cancellations (in shares)					250,372
Common stock issued under employee benefit plans, net of restricted stock cancellations		13,925,000				13,925,000				13,925,000
Net income		247,789,000					233,529,000			233,529,000		14,260,000
Capital calls and distributions, net		(13,792,000)										(13,792,000)
Net change in unrealized gains and losses on AFS securities, net of tax		33,784,000							33,784,000	33,784,000
Amortization of unrealized holding gains on securities transferred from AFS to HTM, net of tax		(100,000)							(100,000)	(100,000)
Foreign currency translation adjustments, net of tax		(40,000)							(40,000)	(40,000)
Net change in unrealized gains and losses on cash flow hedges, net of tax		(11,443,000)							(11,443,000)	(11,443,000)
Share-based compensation, net		20,154,000				20,154,000				20,154,000
Dividends on preferred stock		(4,594,000)					(4,594,000)			(4,594,000)
Other		(591,000)				(591,000)				(591,000)
Balance (in shares) at Jun. 30, 2020					51,740,714
Balance, end of period, net of tax at Jun. 30, 2020		$ 7,468,313,000		$ 340,138	$ 52,000	$ 1,522,728,000	$ 4,841,720,000		$ 614,735,000	$ 7,319,373,000		$ 148,940,000

[1] See "Adoption of New Accounting Standards" in Note 1 — “Basis of Presentation” of the “Notes to Interim Consolidated Financial Statements (unaudited)” under Part I, Item 1 of this report for additional details.