Noninterest Income - Disaggregation of Revenue (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	$ 306	$ 285	$ 633	$ 506
Revenues outside the scope of ASC 606	455	84	872	164
Noninterest income	761	369	1,505	670
Other Items
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	2	0	2	1
Revenues outside the scope of ASC 606	260	50	605	116
Noninterest income	262	50	607	117
Global Commercial Bank
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	154	117	299	267
Revenues outside the scope of ASC 606	20	16	34	33
Noninterest income	174	133	333	300
SVB Private Bank
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1	1	2	1
Revenues outside the scope of ASC 606	0	0	0	0
Noninterest income	1	1	2	1
SVB Capital
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	28	7	41	14
Revenues outside the scope of ASC 606	147	14	203	12
Noninterest income	175	21	244	26
SVB Leerink
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	121	160	289	223
Revenues outside the scope of ASC 606	28	4	30	3
Noninterest income	149	164	319	226
Investment banking revenue
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	15	32	35	75
Investment banking revenue | Other Items
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0	0	0
Investment banking revenue | Global Commercial Bank
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	14	31	33	74
Investment banking revenue | SVB Private Bank
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1	1	2	1
Investment banking revenue | SVB Capital
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0	0	0
Investment banking revenue | SVB Leerink
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0	0	0
Spot contract commissions
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	60	33	115	74
Spot contract commissions | Other Items
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0	0	0
Spot contract commissions | Global Commercial Bank
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	60	33	115	74
Spot contract commissions | SVB Private Bank
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0	0	0
Spot contract commissions | SVB Capital
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0	0	0
Spot contract commissions | SVB Leerink
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0	0	0
Card interchange fees, gross
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	49	26	90	63
Card interchange fees, gross | Other Items
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1	0	1	1
Card interchange fees, gross | Global Commercial Bank
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	48	26	89	62
Card interchange fees, gross | SVB Private Bank
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0	0	0
Card interchange fees, gross | SVB Capital
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0	0	0
Card interchange fees, gross | SVB Leerink
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0	0	0
Merchant service fees
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	4	5	8	10
Merchant service fees | Other Items
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0	0	0
Merchant service fees | Global Commercial Bank
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	4	5	8	10
Merchant service fees | SVB Private Bank
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0	0	0
Merchant service fees | SVB Capital
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0	0	0
Merchant service fees | SVB Leerink
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0	0	0
Deposit service charges
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	28	21	53	45
Deposit service charges | Other Items
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1	0	1	0
Deposit service charges | Global Commercial Bank
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	27	21	52	45
Deposit service charges | SVB Private Bank
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0	0	0
Deposit service charges | SVB Capital
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0	0	0
Deposit service charges | SVB Leerink
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0	0	0
Investment banking revenue
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	103	142	245	188
Investment banking revenue | Other Items
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0	0	0
Investment banking revenue | Global Commercial Bank
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0	0	0
Investment banking revenue | SVB Private Bank
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0	0	0
Investment banking revenue | SVB Capital
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0	0	0
Investment banking revenue | SVB Leerink
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	103	142	245	188
Commissions
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	17	17	41	33
Commissions | Other Items
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0	0	0
Commissions | Global Commercial Bank
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0	0	0
Commissions | SVB Private Bank
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0	0	0
Commissions | SVB Capital
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0	0	0
Commissions | SVB Leerink
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	17	17	41	33
Fund management fees
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	21	8	36	16
Fund management fees | Other Items
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0	0	0
Fund management fees | Global Commercial Bank
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0	0	0
Fund management fees | SVB Private Bank
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0	0	0
Fund management fees | SVB Capital
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	20	7	33	14
Fund management fees | SVB Leerink
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1	1	3	2
Performance fees
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	8		8
Performance fees | Other Items
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0		0
Performance fees | Global Commercial Bank
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0		0
Performance fees | SVB Private Bank
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0		0
Performance fees | SVB Capital
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	8		8
Performance fees | SVB Leerink
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0		0
Correspondent bank rebates
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1	1	2	2
Correspondent bank rebates | Other Items
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0	0	0
Correspondent bank rebates | Global Commercial Bank
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1	1	2	2
Correspondent bank rebates | SVB Private Bank
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0	0	0
Correspondent bank rebates | SVB Capital
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0	0	0
Correspondent bank rebates | SVB Leerink
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	$ 0	$ 0	$ 0	$ 0