Annual report pursuant to Section 13 and 15(d)

DEBT SECURITIES (Summary Information About Sales Of Debt Securities Available For Sale) (Detail)

v2.4.1.9
DEBT SECURITIES (Summary Information About Sales Of Debt Securities Available For Sale) (Detail) (USD $)
In Thousands, unless otherwise specified
12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Sale proceeds $ 173us-gaap_ProceedsFromSaleOfAvailableForSaleSecurities $ 4,140us-gaap_ProceedsFromSaleOfAvailableForSaleSecurities $ 0us-gaap_ProceedsFromSaleOfAvailableForSaleSecurities
Gross realized gains 3sfbs_GainOnSaleOfSecuritiesNet 131sfbs_GainOnSaleOfSecuritiesNet 0sfbs_GainOnSaleOfSecuritiesNet
Gross realized losses 0sfbs_LossOnSaleOfSecuritiesNet 0sfbs_LossOnSaleOfSecuritiesNet 0sfbs_LossOnSaleOfSecuritiesNet
Net realized gain (loss) $ 3us-gaap_GainLossOnSaleOfSecuritiesNet $ 131us-gaap_GainLossOnSaleOfSecuritiesNet $ 0us-gaap_GainLossOnSaleOfSecuritiesNet