Total Capital Commitments, Unfunded Capital Commitments, and Our Ownership in Each Fund (Parenthetical) (Detail) (USD $) In Thousands, unless otherwise specified	9 Months Ended		12 Months Ended
	Sep. 30, 2011		Dec. 31, 2010
Long-term Purchase Commitment [Line Items]
Unfunded Commitments	314,285
Investment company fair value accounting | Direct ownership interest | Venture capital and private equity fund investments | SVB Capital Partners II, LP
Long-term Purchase Commitment [Line Items]
Percentage of ownership	1.30%
Investment company fair value accounting | Direct ownership interest | Venture capital and private equity fund investments | Other private equity fund
Long-term Purchase Commitment [Line Items]
Percentage of ownership	41.50%
Equity method accounting | Direct ownership interest | Other investments | Gold Hill Venture Lending 03, LP
Long-term Purchase Commitment [Line Items]
Percentage of ownership	4.80%
Investment company fair value accounting | Indirect ownership interest | Venture capital and private equity fund investments | SVB Capital Preferred Return Fund, LP
Long-term Purchase Commitment [Line Items]
Percentage of ownership	4.10%
Investment company fair value accounting | Indirect ownership interest | Venture capital and private equity fund investments | SVB Capital-NT Growth Partners, LP
Long-term Purchase Commitment [Line Items]
Percentage of ownership	12.60%
Investment company fair value accounting | Indirect ownership interest | Venture capital and private equity fund investments | SVB Capital Partners II, LP
Long-term Purchase Commitment [Line Items]
Percentage of ownership	3.80%
Equity method accounting | Indirect ownership interest | Other investments | Gold Hill Venture Lending 03, LP
Long-term Purchase Commitment [Line Items]
Percentage of ownership	4.50%
Investment company fair value accounting | Venture capital and private equity fund investments | SVB Capital Partners II, LP
Long-term Purchase Commitment [Line Items]
Percentage of ownership	5.10%	[1]	5.10%	[1]
Investment company fair value accounting | Venture capital and private equity fund investments | SVB Capital Preferred Return Fund, LP
Long-term Purchase Commitment [Line Items]
Percentage of ownership	20.00%		20.00%
SVB Capital Preferred Return Fund, LP
Long-term Purchase Commitment [Line Items]
Unfunded Commitments	27,053
Investment company fair value accounting | Venture capital and private equity fund investments | SVB Capital-NT Growth Partners, LP
Long-term Purchase Commitment [Line Items]
Percentage of ownership	33.00%		33.00%
SVB Capital-NT Growth Partners, LP
Long-term Purchase Commitment [Line Items]
Unfunded Commitments	30,510
Investment company fair value accounting | Venture capital and private equity fund investments | Other private equity fund
Long-term Purchase Commitment [Line Items]
Percentage of ownership	58.20%	[2]	60.60%	[2]
Other private equity fund
Long-term Purchase Commitment [Line Items]
Unfunded Commitments	5,250
Equity method accounting | Other investments | Gold Hill Venture Lending 03, LP
Long-term Purchase Commitment [Line Items]
Percentage of ownership	9.30%	[3]	9.30%	[3]
Venture capital and private equity fund investments | Upper Limit | Other Fund Investments
Long-term Purchase Commitment [Line Items]
Percentage of ownership	5.00%
Venture capital and private equity fund investments | Other Fund Investments
Long-term Purchase Commitment [Line Items]
Number of other funds with investment commitments	334
Other Fund Investments
Long-term Purchase Commitment [Line Items]
Capital Commitments	180,100
Unfunded Commitments	74,900

[1] At September 30, 2011, we had a direct ownership interest of 1.3% and an indirect ownership interest of 3.8% in the fund through our ownership interest of SVB Strategic Investors Fund II, LP.

[2] At September 30, 2011, we had a direct ownership interest of 41.5% and indirect ownership interests of 12.6% and 4.1% in the fund through our ownership interests of SVB Capital-NT Growth Partners, LP and SVB Capital Preferred Return Fund, LP, respectively.

[3] At September 30, 2011, we had a direct ownership interest of 4.8% in the fund and an indirect interest in the fund through our investment in Gold Hill Venture Lending Partners 03, LLC ("GHLLC") of 4.5%. Our aggregate direct and indirect ownership in the fund is 9.3%.