Reconciliation of Basic EPS to Diluted EPS (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010	Sep. 30, 2010	Jun. 30, 2010	Mar. 31, 2010	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Numerator:
Net income attributable to SVBFG									$ 171,902	$ 94,951	$ 48,010
Preferred stock dividend and discount accretion											(25,336)
Net income available to common stockholders	$ 35,574	$ 37,571	$ 65,750	$ 33,007	$ 17,487	$ 37,787	$ 21,120	$ 18,557	$ 171,902	$ 94,951	$ 22,674
Denominator:
Weighted average common shares outstanding-basic									43,004	41,774	33,901
Denominator for diluted calculation									43,637	42,478	34,183
Net income per common share:
Basic	$ 0.82	$ 0.87	$ 1.53	$ 0.78	$ 0.42	$ 0.90	$ 0.51	$ 0.45	$ 4.00	$ 2.27	$ 0.67
Diluted	$ 0.81	$ 0.86	$ 1.50	$ 0.76	$ 0.41	$ 0.89	$ 0.50	$ 0.44	$ 3.94	$ 2.24	$ 0.66
Stock options and ESPP
Denominator:
Weighted average effect of dilutive securities									517	641	282
Restricted stock units
Denominator:
Weighted average effect of dilutive securities									116	63