Noninterest Income - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	$ 222,440	$ 217,257
Revenues outside the scope of ASC 606	79,494	63,119
Noninterest income	301,934	280,376
Global Commercial Bank
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	149,803	144,417
Revenues outside the scope of ASC 606	17,031	8,444
Noninterest income	166,834	152,861
SVB Private Bank
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	852	537
Revenues outside the scope of ASC 606	48	(27)
Noninterest income	900	510
SVB Capital
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	6,478	6,659
Revenues outside the scope of ASC 606	(1,560)	18,186
Noninterest income	4,918	24,845
SVB Leerink
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	64,319	65,285
Revenues outside the scope of ASC 606	(1,642)	2,832
Noninterest income	62,677	68,117
Other Items
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	988	359
Revenues outside the scope of ASC 606	65,617	33,684
Noninterest income	66,605	34,043
Investment banking revenue
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	43,393	44,482
Investment banking revenue | Global Commercial Bank
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	42,736	44,102
Investment banking revenue | SVB Private Bank
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	657	380
Investment banking revenue | SVB Capital
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0
Investment banking revenue | SVB Leerink
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0
Investment banking revenue | Other Items
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0
Spot contract commissions
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	40,934	35,029
Spot contract commissions | Global Commercial Bank
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	40,675	34,806
Spot contract commissions | SVB Private Bank
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	161	122
Spot contract commissions | SVB Capital
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0
Spot contract commissions | SVB Leerink
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0
Spot contract commissions | Other Items
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	98	101
Card interchange fees, gross
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	36,297	38,862
Card interchange fees, gross | Global Commercial Bank
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	35,724	38,715
Card interchange fees, gross | SVB Private Bank
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	7	0
Card interchange fees, gross | SVB Capital
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0
Card interchange fees, gross | SVB Leerink
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0
Card interchange fees, gross | Other Items
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	566	147
Merchant service fees
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	5,027	4,534
Merchant service fees | Global Commercial Bank
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	5,027	4,534
Merchant service fees | SVB Private Bank
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0
Merchant service fees | SVB Capital
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0
Merchant service fees | SVB Leerink
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0
Merchant service fees | Other Items
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0
Deposit service charges
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	24,589	20,939
Deposit service charges | Global Commercial Bank
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	24,238	20,793
Deposit service charges | SVB Private Bank
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	27	35
Deposit service charges | SVB Capital
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0
Deposit service charges | SVB Leerink
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0
Deposit service charges | Other Items
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	324	111
Investment banking revenue
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	46,867	49,795
Investment banking revenue | Global Commercial Bank
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0
Investment banking revenue | SVB Private Bank
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0
Investment banking revenue | SVB Capital
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0
Investment banking revenue | SVB Leerink
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	46,867	49,795
Investment banking revenue | Other Items
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0
Commissions
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	16,022	14,108
Commissions | Global Commercial Bank
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0
Commissions | SVB Private Bank
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0
Commissions | SVB Capital
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0
Commissions | SVB Leerink
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	16,022	14,108
Commissions | Other Items
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0
Fund management fees
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	7,908	8,041
Fund management fees | Global Commercial Bank
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0
Fund management fees | SVB Private Bank
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0
Fund management fees | SVB Capital
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	6,478	6,659
Fund management fees | SVB Leerink
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1,430	1,382
Fund management fees | Other Items
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	1,403	1,467
Correspondent bank rebates | Global Commercial Bank
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1,403	1,467
Correspondent bank rebates | SVB Private Bank
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0
Correspondent bank rebates | SVB Capital
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0
Correspondent bank rebates | SVB Leerink
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0
Correspondent bank rebates | Other Items
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	$ 0	$ 0