Interim Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Statement of Comprehensive Income [Abstract]
Net income before noncontrolling interests	$ 628	$ 248	$ 1,190	$ 381
Change in foreign currency cumulative translation gains and losses:
Foreign currency translation gains (losses)	2	0	2	(9)
Related tax (expense) benefit	(1)	0	(1)	2
Change in unrealized gains and losses on available-for-sale securities:
Unrealized holding gains (losses)	270	47	(554)	591
Related tax (expense) benefit	(75)	(13)	154	(164)
Reclassification adjustment for gains included in net income	0	0	0	(61)
Related tax expense	0	0	0	17
Cumulative-effect adjustment for unrealized losses on securities transferred from AFS to HTM	(87)	0	(78)	0
Related tax benefit	25	0	22	0
Amortization of unrealized holding net gains on securities transferred from AFS to HTM	(2)	0	(5)	(1)
Related tax expense	0	0	1	0
Change in unrealized gains and losses on cash flow hedges:
Unrealized gains	0	0	0	232
Related tax expense	0	0	0	(64)
Reclassification adjustment for gains included in net income	(16)	(16)	(31)	(18)
Related tax expense	5	4	9	5
Other comprehensive income (loss), net of tax	121	22	(481)	530
Comprehensive income	749	270	709	911
Comprehensive income attributable to noncontrolling interests	(113)	(14)	(138)	(12)
Comprehensive income attributable to SVBFG	$ 636	$ 256	$ 571	$ 899