Average Required Reserve Balances (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010
Reserves on Deposit with Federal Reserve Bank and Federal Home Loan Bank [Line Items]
Average required reserve balances at FRB San Francisco	$ 91,046	$ 46,929

Federal Reserve Bank with Average Reserve Required

No definition available.

Name:	sivb_FederalReserveBankWithAverageReserveRequired
Namespace Prefix:	sivb_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration