Remaining Unfunded Commitments to Venture Capital or Private Equity Funds by our Consolidated Managed Funds (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012
Commitments and Contingencies Disclosure [Line Items]
Unfunded Commitments	$ 431,837
SVB Strategic Investors Fund, LP
Commitments and Contingencies Disclosure [Line Items]
Unfunded Commitments	2,307
SVB Strategic Investors Fund II, LP
Commitments and Contingencies Disclosure [Line Items]
Unfunded Commitments	9,262
SVB Strategic Investors Fund III, LP
Commitments and Contingencies Disclosure [Line Items]
Unfunded Commitments	38,005
SVB Strategic Investors Fund IV, LP
Commitments and Contingencies Disclosure [Line Items]
Unfunded Commitments	93,754
Strategic Investors Fund V Funds
Commitments and Contingencies Disclosure [Line Items]
Unfunded Commitments	251,235
SVB Capital Preferred Return Fund, LP
Commitments and Contingencies Disclosure [Line Items]
Unfunded Commitments	17,342
SVB Capital-NT Growth Partners, LP
Commitments and Contingencies Disclosure [Line Items]
Unfunded Commitments	15,704
Other private equity fund
Commitments and Contingencies Disclosure [Line Items]
Unfunded Commitments	$ 4,228