Loans and Allowance for Loan Losses Allowance for Loan Losses Individually and Collectively Evaluated for Impairment (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Financing Receivable, Impaired [Line Items]
Individually Evaluated for Impairment	$ 21,277	$ 6,261
Collectively Evaluated for Impairment	121,609	104,390
Software
Financing Receivable, Impaired [Line Items]
Individually Evaluated for Impairment	11,261	762
Collectively Evaluated for Impairment	52,823	41,886
Hardware
Financing Receivable, Impaired [Line Items]
Individually Evaluated for Impairment	9,673	5,251
Collectively Evaluated for Impairment	26,880	24,510
Venture capital/private equity
Financing Receivable, Impaired [Line Items]
Individually Evaluated for Impairment	19	0
Collectively Evaluated for Impairment	16,366	9,963
Life science
Financing Receivable, Impaired [Line Items]
Individually Evaluated for Impairment	0	0
Collectively Evaluated for Impairment	11,926	13,606
Premium wine
Financing Receivable, Impaired [Line Items]
Individually Evaluated for Impairment	0	0
Collectively Evaluated for Impairment	3,914	3,523
Commercial, Other
Financing Receivable, Impaired [Line Items]
Individually Evaluated for Impairment	156	0
Collectively Evaluated for Impairment	3,524	3,912
Commercial loans
Financing Receivable, Impaired [Line Items]
Individually Evaluated for Impairment	21,109	6,013
Collectively Evaluated for Impairment	115,433	97,400
Consumer loans
Financing Receivable, Impaired [Line Items]
Individually Evaluated for Impairment	168	248
Collectively Evaluated for Impairment	$ 6,176	$ 6,990