Interim Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Statement of Comprehensive Income [Abstract]
Net income before noncontrolling interests	$ 247,789	$ 336,571	$ 381,438	$ 628,183
Change in foreign currency cumulative translation gains and losses:
Foreign currency translation gains (losses)	164	(2,900)	(8,956)	(94)
Related tax (expense) benefit	(204)	808	2,352	26
Change in unrealized gains and losses on available-for-sale securities:
Unrealized holding gains	46,738	119,182	590,619	166,018
Related tax expense	(12,954)	(33,194)	(163,700)	(46,239)
Reclassification adjustment for losses (gains) included in net income	0	275	(61,165)	3,905
Related tax (benefit) expense	0	(77)	16,953	(1,087)
Amortization of unrealized holding gains on securities transferred from available-for-sale to held-to-maturity	(138)	(719)	(690)	(1,393)
Related tax benefit	38	200	191	388
Change in unrealized gains and losses on cash flow hedges:
Unrealized gains	0	17,554	231,920	18,656
Related tax expense	0	(4,890)	(64,281)	(5,197)
Reclassification adjustment for (gains) losses included in net income	(15,831)	508	(17,920)	511
Related tax expense (benefit)	4,388	(141)	4,967	(142)
Other comprehensive income, net of tax	22,201	96,606	530,290	135,352
Comprehensive income	269,990	433,177	911,728	763,535
Comprehensive income attributable to noncontrolling interests	(14,260)	(18,584)	(12,287)	(21,464)
Comprehensive income attributable to SVBFG	$ 255,730	$ 414,593	$ 899,441	$ 742,071