Total Capital Commitments, Unfunded Capital Commitments, and Our Ownership in Each Fund (Parenthetical) (Detail)	6 Months Ended		12 Months Ended
	Jun. 30, 2012		Dec. 31, 2011
SVB Capital Partners II, LP | Fair value accounting | Venture capital and private equity fund investments
Venture Capital and Private Equity Fund Investments [Line Items]
Percentage of ownership	5.10%	[1]	5.10%	[1]
SVB Capital Partners II, LP | Fair value accounting | Direct ownership interest | Venture capital and private equity fund investments
Venture Capital and Private Equity Fund Investments [Line Items]
Percentage of ownership	1.30%
SVB Capital Partners II, LP | Fair value accounting | Indirect ownership interest | Venture capital and private equity fund investments
Venture Capital and Private Equity Fund Investments [Line Items]
Percentage of ownership	3.80%
Other private equity fund | Fair value accounting | Venture capital and private equity fund investments
Venture Capital and Private Equity Fund Investments [Line Items]
Percentage of ownership	58.20%	[2]	58.20%	[2]
Other private equity fund | Fair value accounting | Direct ownership interest | Venture capital and private equity fund investments
Venture Capital and Private Equity Fund Investments [Line Items]
Percentage of ownership	41.50%
Gold Hill Venture Lending 03, LP | Equity method accounting | Other investments
Venture Capital and Private Equity Fund Investments [Line Items]
Percentage of ownership	9.30%	[3]	9.30%	[3]
Gold Hill Venture Lending 03, LP | Equity method accounting | Direct ownership interest | Other investments
Venture Capital and Private Equity Fund Investments [Line Items]
Percentage of ownership	4.80%
Gold Hill Venture Lending 03, LP | Equity method accounting | Indirect ownership interest | Other investments
Venture Capital and Private Equity Fund Investments [Line Items]
Percentage of ownership	4.50%
Other Fund Investments | Venture capital and private equity fund investments
Venture Capital and Private Equity Fund Investments [Line Items]
Number of other funds with investment commitments	332
Upper Limit | Other Fund Investments | Venture capital and private equity fund investments
Venture Capital and Private Equity Fund Investments [Line Items]
Percentage of ownership	5.00%
SVB Capital-NT Growth Partners, LP | Other private equity fund | Fair value accounting | Indirect ownership interest | Venture capital and private equity fund investments
Venture Capital and Private Equity Fund Investments [Line Items]
Percentage of ownership	12.60%
SVB Capital Preferred Return Fund, LP | Other private equity fund | Fair value accounting | Indirect ownership interest | Venture capital and private equity fund investments
Venture Capital and Private Equity Fund Investments [Line Items]
Percentage of ownership	4.10%

[1] At June 30, 2012, we had a direct ownership interest of 1.3 percent and an indirect ownership interest of 3.8 percent in the fund through our ownership interest of SVB Strategic Investors Fund II, LP.

[2] At June 30, 2012, we had a direct ownership interest of 41.5 percent and indirect ownership interests of 12.6 percent and 4.1 percent in the fund through our ownership interest of SVB Capital-NT Growth Partners, LP and SVB Capital Preferred Return Fund, LP, respectively.

[3] At June 30, 2012, we had a direct ownership interest of 4.8 percent 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 percent. Our aggregate direct and indirect ownership in the fund is 9.3 percent.