Parent Company Only Condensed Financial Information Condensed Balance Sheet (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Assets:
Cash and cash equivalents	$ 1,538,779	$ 1,008,983	$ 1,114,948	$ 3,076,432
Investment securities	13,582,315	12,527,442
Net loans	10,763,500	8,836,282
Other assets	465,110	326,871
Total assets	26,417,189	22,766,123
Liabilities and total equity
Other liabilities	404,586	360,566
Total liabilities	23,337,861	20,160,890
SVBFG stockholders' equity	1,966,270	1,830,555
Total liabilities and total equity	26,417,189	22,766,123
Parent Company
Assets:
Cash and cash equivalents	218,148	169,067	137,185	433,661
Investment securities	234,398	252,858
Net loans	4,791	8,869
Other assets	136,897	116,596
Total assets	2,393,529	2,255,804
Liabilities and total equity
Other liabilities	24,030	22,058
Total liabilities	427,259	425,249
SVBFG stockholders' equity	1,966,270	1,830,555
Total liabilities and total equity	2,393,529	2,255,804
Parent Company | 5.375% Senior Notes
Liabilities and total equity
Notes payable	348,209	347,995
Parent Company | 7.0% Junior Subordinated Debentures
Liabilities and total equity
Notes payable	55,020	55,196
Parent Company | Bank Subsidiaries
Assets:
Investment in subsidiaries	1,639,024	1,592,987
Parent Company | Nonbank Subsidiaries
Assets:
Investment in subsidiaries	$ 160,271	$ 115,427