Interim Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Statement of Comprehensive Income [Abstract]
Net income before noncontrolling interests	$ 475	$ 474	$ 1,665	$ 855
Change in foreign currency cumulative translation gains and losses:
Foreign currency translation (losses) gains	(6)	10	(4)	1
Related tax benefit (expense)	2	(3)	1	0
Change in unrealized gains and losses on available-for-sale securities:
Unrealized holding (losses) gains	(30)	14	(584)	605
Related tax benefit (expense)	8	(4)	163	(168)
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	(54)	0	(132)	0
Related tax benefit	15	0	36	0
Amortization of unrealized holding net gains on securities transferred from AFS to HTM	0	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)	(47)	(34)
Related tax expense	4	5	13	9
Other comprehensive (loss) income, net of tax	(77)	6	(558)	536
Comprehensive income	398	480	1,107	1,391
Comprehensive income attributable to noncontrolling interests	(88)	(28)	(226)	(40)
Comprehensive income attributable to SVBFG	$ 310	$ 452	$ 881	$ 1,351