Allowance for Loan and Lease Losses (Narrative) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Accounts, Notes, Loans and Financing Receivable [Line Items]
Troubled debt restructuring reserves amount	$ 2,605	$ 2,714
Percentage collateral to impaired loan balances	92.00%
General	$ 5,449	$ 5,800

Loans and Leases Receivable Allowance, General Reserves

No definition available.

Name:	bsrr_LoansAndLeasesReceivableAllowanceGeneralReserves
Namespace Prefix:	bsrr_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant