Off-Balance Sheet Arrangements, Guarantees and Other Commitments - Commitments to Invest in Venture Capital and Private Equity Funds (Details) - Parent Company $ in Millions	3 Months Ended
	Jun. 30, 2022 USD ($)
Commitments and Contingencies Disclosure [Line Items]
SVBFG Capital Commitments	$ 671
SVBFG Unfunded Commitments	172
Redwood Evergreen Fund, LP
Commitments and Contingencies Disclosure [Line Items]
SVBFG Capital Commitments	250
SVBFG Unfunded Commitments	$ 150
SVBFG Ownership of each Fund	100.00%
Capital Preferred Return Fund, LP
Commitments and Contingencies Disclosure [Line Items]
SVBFG Capital Commitments	$ 13
SVBFG Unfunded Commitments	$ 0
SVBFG Ownership of each Fund	20.00%
Growth Partners, LP
Commitments and Contingencies Disclosure [Line Items]
SVBFG Capital Commitments	$ 25
SVBFG Unfunded Commitments	$ 1
SVBFG Ownership of each Fund	33.00%
Strategic Investors Fund, LP
Commitments and Contingencies Disclosure [Line Items]
SVBFG Capital Commitments	$ 15
SVBFG Unfunded Commitments	$ 1
SVBFG Ownership of each Fund	12.60%
CP II, LP
Commitments and Contingencies Disclosure [Line Items]
SVBFG Capital Commitments	$ 1
SVBFG Unfunded Commitments	$ 0
SVBFG Ownership of each Fund	5.10%
Strategic Investors Fund II, LP
Commitments and Contingencies Disclosure [Line Items]
SVBFG Capital Commitments	$ 15
SVBFG Unfunded Commitments	$ 1
SVBFG Ownership of each Fund	8.60%
Strategic Investors Fund III, LP
Commitments and Contingencies Disclosure [Line Items]
SVBFG Capital Commitments	$ 15
SVBFG Unfunded Commitments	$ 1
SVBFG Ownership of each Fund	5.90%
Strategic Investors Fund IV, LP
Commitments and Contingencies Disclosure [Line Items]
SVBFG Capital Commitments	$ 12
SVBFG Unfunded Commitments	$ 2
SVBFG Ownership of each Fund	5.00%
Strategic Investors Fund V funds
Commitments and Contingencies Disclosure [Line Items]
SVBFG Capital Commitments	$ 1
SVBFG Unfunded Commitments	0
Other venture capital and private equity fund investments
Commitments and Contingencies Disclosure [Line Items]
SVBFG Capital Commitments	17
SVBFG Unfunded Commitments	5
Debt funds (equity method accounting)
Commitments and Contingencies Disclosure [Line Items]
SVBFG Capital Commitments	59
SVBFG Unfunded Commitments	0
Other fund investments
Commitments and Contingencies Disclosure [Line Items]
SVBFG Capital Commitments	248
SVBFG Unfunded Commitments	$ 11