Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Statement of Comprehensive Income [Abstract]
Net income before noncontrolling interests		$ 1,011,348	$ 519,178	$ 390,266
Change in foreign currency cumulative translation gains and losses:
Foreign currency translation (losses) gains		(5,999)	6,355	(5,245)
Related tax benefit (expense)		1,669	(2,587)	2,050
Change in unrealized gains and losses on available-for-sale securities:
Unrealized holding (losses) gains		(22,348)	(47,161)	39,016
Related tax benefit (expense)		6,315	19,282	(15,911)
Reclassification adjustment for losses (gains) included in net income	[1]	740	5,189	(12,195)
Related tax (benefit) expense	[1]	(205)	(2,098)	4,963
Reclassification of unrealized gains on equity securities to retained earnings for ASU 2016-01	[1]	(40,316)	0	0
Related tax expense	[1]	11,145	0	0
Amortization of unrealized gains on securities transferred from available-for-sale to held-to-maturity		(4,607)	(6,475)	(7,786)
Related tax benefit		1,277	2,593	3,134
Reclassification of stranded tax effect to retained earnings for ASU 2018-02	[1]	(319)	0	0
Other comprehensive (loss) income, net of tax		(52,648)	(24,902)	8,026
Comprehensive income		958,700	494,276	398,292
Comprehensive income attributable to noncontrolling interests		(37,508)	(28,672)	(7,581)
Comprehensive income attributable to SVBFG		$ 921,192	$ 465,604	$ 390,711

[1] See Note 2- "Summary of Significant Accounting Policies" of the "Notes to Consolidated Financial Statements" under Part II, Item 8 of this report for additional details.