Off-Balance Sheet Arrangements, Guarantees and Other Commitments - Remaining Unfunded Commitments to Venture Capital or Private Equity Funds by our Consolidated Managed Funds (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014
Commitments and Contingencies Disclosure [Line Items]
SVBFG Unfunded Commitments	$ 436,465
SVB Strategic Investors Fund, LP
Commitments and Contingencies Disclosure [Line Items]
SVBFG Unfunded Commitments	2,250
SVB Strategic Investors Fund II, LP
Commitments and Contingencies Disclosure [Line Items]
SVBFG Unfunded Commitments	6,409
SVB Strategic Investors Fund III, LP
Commitments and Contingencies Disclosure [Line Items]
SVBFG Unfunded Commitments	20,214
SVB Strategic Investors Fund IV, LP
Commitments and Contingencies Disclosure [Line Items]
SVBFG Unfunded Commitments	54,430
Strategic Investors Fund V Funds
Commitments and Contingencies Disclosure [Line Items]
SVBFG Unfunded Commitments	202,688
Strategic Investors Fund VI Funds
Commitments and Contingencies Disclosure [Line Items]
SVBFG Unfunded Commitments	130,846
SVB Capital Preferred Return Fund, LP
Commitments and Contingencies Disclosure [Line Items]
SVBFG Unfunded Commitments	9,075
SVB Capital—NT Growth Partners, LP
Commitments and Contingencies Disclosure [Line Items]
SVBFG Unfunded Commitments	10,310
Other private equity fund
Commitments and Contingencies Disclosure [Line Items]
SVBFG Unfunded Commitments	$ 243