Parent Company Only Condensed Financial Information Condensed Statement of Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Net income available to common stockholders	$ 99,466	$ 111,081	$ 92,964	$ 79,174	$ 87,512	$ 81,733	$ 86,143	$ 88,516	$ 382,685	$ 343,904	$ 263,870
Other comprehensive income (loss), net of tax									8,026	(27,300)	91,468
Comprehensive income attributable to SVBFG									390,711	316,604	355,338
Parent Company
Net income available to common stockholders									382,685	343,904	263,870
Foreign currency translation gains (losses)									3,071	(1,492)	3,012
Unrealized holding gains (losses) on securities available for sale									654	(2,041)	1,232
Equity in other comprehensive income (losses) of subsidiaries									4,301	(23,767)	87,224
Other comprehensive income (loss), net of tax									8,026	(27,300)	91,468
Comprehensive income attributable to SVBFG									$ 390,711	$ 316,604	$ 355,338