Summary of Significant Accounting Policies Summary of Ownership Interests in Investments Held Under Fair Value Accounting (Detail) (Fair value accounting)	12 Months Ended
	Dec. 31, 2013		Dec. 31, 2012
Venture capital and private equity fund investments | SVB Strategic Investors Fund, LP
Schedule of Investments [Line Items]
Company Direct and Indirect Ownership in Limited Partnership	12.60%		12.60%
Venture capital and private equity fund investments | SVB Strategic Investors Fund II, LP
Schedule of Investments [Line Items]
Company Direct and Indirect Ownership in Limited Partnership	8.60%		8.60%
Venture capital and private equity fund investments | SVB Strategic Investors Fund III, LP
Schedule of Investments [Line Items]
Company Direct and Indirect Ownership in Limited Partnership	5.90%		5.90%
Venture capital and private equity fund investments | SVB Strategic Investors Fund IV, LP
Schedule of Investments [Line Items]
Company Direct and Indirect Ownership in Limited Partnership	5.00%		5.00%
Venture capital and private equity fund investments | Strategic Investors Fund VI Funds
Schedule of Investments [Line Items]
Company Direct and Indirect Ownership in Limited Partnership	0.20%		0.00%
Venture capital and private equity fund investments | SVB Capital Preferred Return Fund, LP
Schedule of Investments [Line Items]
Company Direct and Indirect Ownership in Limited Partnership	20.00%		20.00%
Venture capital and private equity fund investments | SVB Capital-NT Growth Partners, LP
Schedule of Investments [Line Items]
Company Direct and Indirect Ownership in Limited Partnership	33.00%		33.00%
Venture capital and private equity fund investments | Other private equity fund
Schedule of Investments [Line Items]
Company Direct and Indirect Ownership in Limited Partnership	58.20%	[1]	58.20%
Venture capital and private equity fund investments | SVB Capital Partners II, LP
Schedule of Investments [Line Items]
Company Direct and Indirect Ownership in Limited Partnership	5.10%	[2]	5.10%
Other venture capital investments | Silicon Valley BancVentures, LP
Schedule of Investments [Line Items]
Company Direct and Indirect Ownership in Limited Partnership	10.70%		10.70%
Other venture capital investments | SVB Capital Partners II, LP
Schedule of Investments [Line Items]
Company Direct and Indirect Ownership in Limited Partnership	5.10%	[3]	5.10%
Other venture capital investments | SVB Capital Shanghai Yangpu Venture Capital Fund
Schedule of Investments [Line Items]
Company Direct and Indirect Ownership in Limited Partnership	6.80%		6.80%

[1] At December 31, 2013, 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

[2] At December 31, 2013, 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.

[3] At December 31, 2013, 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 of SVB Strategic Investors Fund II, LP.