Off-Balance Sheet Arrangements, Guarantees and Other Commitments - Total Capital Commitments, Unfunded Capital Commitments, and Our Ownership in Each Fund (Details) $ in Millions	12 Months Ended
	Dec. 31, 2021 USD ($) Investment
Other Commitments [Line Items]
SVBFG Unfunded Commitments	$ 3
Capital Preferred Return Fund, LP
Other Commitments [Line Items]
SVBFG Unfunded Commitments	2
Growth Partners, LP
Other Commitments [Line Items]
SVBFG Unfunded Commitments	$ 1
Consolidated venture capital and private equity fund investments
Other Commitments [Line Items]
Commitments expiration period	10 years
Consolidated venture capital and private equity fund investments | CP II, LP | Non-marketable securities | Direct ownership interest
Other Commitments [Line Items]
SVBFG Ownership interest percentage	1.30%
Consolidated venture capital and private equity fund investments | CP II, LP | Non-marketable securities | Indirect ownership interest
Other Commitments [Line Items]
SVBFG Ownership interest percentage	3.80%
Consolidated venture capital and private equity fund investments | Other fund investments | Non-marketable securities
Other Commitments [Line Items]
Number of other funds with investment commitments | Investment	156
Upper Limit
Other Commitments [Line Items]
SVBFG Ownership interest percentage	5.00%
Upper Limit | Consolidated venture capital and private equity fund investments
Other Commitments [Line Items]
Fund commitments investment cycle	7 years
Upper Limit | Consolidated venture capital and private equity fund investments | Other fund investments | Non-marketable securities
Other Commitments [Line Items]
SVBFG Ownership interest percentage	5.00%
Lower Limit | Consolidated venture capital and private equity fund investments
Other Commitments [Line Items]
Fund commitments investment cycle	5 years
Parent Company
Other Commitments [Line Items]
SVBFG Capital Commitments	$ 420
SVBFG Unfunded Commitments	22
Parent Company | CP II, LP
Other Commitments [Line Items]
SVBFG Capital Commitments	1
SVBFG Unfunded Commitments	$ 0
SVBFG Ownership interest percentage	5.10%
Parent Company | Strategic Investors Fund II, LP
Other Commitments [Line Items]
SVBFG Capital Commitments	$ 15
SVBFG Unfunded Commitments	$ 1
SVBFG Ownership interest percentage	8.60%
Parent Company | Strategic Investors Fund III, LP
Other Commitments [Line Items]
SVBFG Capital Commitments	$ 15
SVBFG Unfunded Commitments	$ 1
SVBFG Ownership interest percentage	5.90%
Parent Company | Strategic Investors Fund IV, LP
Other Commitments [Line Items]
SVBFG Capital Commitments	$ 12
SVBFG Unfunded Commitments	$ 2
SVBFG Ownership interest percentage	5.00%
Parent Company | Strategic Investors Fund V funds
Other Commitments [Line Items]
SVBFG Capital Commitments	$ 1
SVBFG Unfunded Commitments	0
Parent Company | Other venture capital and private equity fund investments
Other Commitments [Line Items]
SVBFG Capital Commitments	17
SVBFG Unfunded Commitments	6
Parent Company | Debt funds (equity method accounting)
Other Commitments [Line Items]
SVBFG Capital Commitments	59
SVBFG Unfunded Commitments	0
Parent Company | Other fund investments
Other Commitments [Line Items]
SVBFG Capital Commitments	247
SVBFG Unfunded Commitments	10
Parent Company | Capital Preferred Return Fund, LP
Other Commitments [Line Items]
SVBFG Capital Commitments	13
SVBFG Unfunded Commitments	$ 0
SVBFG Ownership interest percentage	20.00%
Parent Company | Growth Partners, LP
Other Commitments [Line Items]
SVBFG Capital Commitments	$ 25
SVBFG Unfunded Commitments	$ 1
SVBFG Ownership interest percentage	33.00%
Parent Company | Strategic Investors Fund, LP
Other Commitments [Line Items]
SVBFG Capital Commitments	$ 15
SVBFG Unfunded Commitments	$ 1
SVBFG Ownership interest percentage	12.60%