Gross amount of transition impact of allowances for credit losses.

No definition available.

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

- Definition

Amount of impact of allowances for credit losses on reserves under CECL.

+ References

No definition available.

+ Details

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

- Definition

Amount of impact of allowances for credit losses on reserves under incurred loss.

+ References

No definition available.

+ Details

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

- Definition

Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, without jurisdictional netting.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 2
-URI https://asc.fasb.org/extlink&oid=121826272&loc=d3e32537-109319

+ Details

Name:	us-gaap_DeferredTaxAssetsLiabilitiesNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The cumulative amount of the reporting entity's undistributed earnings or deficit.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(30)(a)(3))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 852
-SubTopic 10
-Section 55
-Paragraph 10
-URI https://asc.fasb.org/extlink&oid=84165509&loc=d3e56426-112766

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(23)(a)(4))
-URI https://asc.fasb.org/extlink&oid=126734703&loc=d3e572229-122910

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 40
-Section 65
-Paragraph 2
-Subparagraph (h)(2)
-URI https://asc.fasb.org/extlink&oid=124501264&loc=SL117420844-207641

Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI https://asc.fasb.org/extlink&oid=120397183&loc=d3e187085-122770

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 40
-Section 65
-Paragraph 2
-Subparagraph (g)(2)(i)
-URI https://asc.fasb.org/extlink&oid=124501264&loc=SL117420844-207641

+ Details

Name:	us-gaap_RetainedEarningsAccumulatedDeficit
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Current Accounting Developments - Transition Impact on Allowance for Credit Losses - Tabular Disclosure (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Jan. 01, 2022	Dec. 31, 2021
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Impact to Retained Earnings	$ 239,496		$ 234,410
Accounting Standards Update 2016-13 [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Impact to Retained Earnings		$ 7,300
Accounting Standards Update 2016-13 [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member] \| Consumer Portfolio Segment [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reserves Under Incurred Loss		521
Reserves Under CECL		279
Transition Impact Gross		(242)
Impact of Deferred Taxes		72
Impact to Retained Earnings		(170)
Accounting Standards Update 2016-13 [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member] \| Mortgage Warehouse Lines [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reserves Under Incurred Loss		512
Reserves Under CECL		91
Transition Impact Gross		(421)
Impact of Deferred Taxes		124
Impact to Retained Earnings		(297)
Accounting Standards Update 2016-13 [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member] \| Loans Receivable [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reserves Under Incurred Loss		14,256
Reserves Under CECL		23,710
Transition Impact Gross		9,454
Impact of Deferred Taxes		(2,795)
Impact to Retained Earnings		6,659
Accounting Standards Update 2016-13 [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member] \| Unfunded Loan Commitment [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reserves Under Incurred Loss		203
Reserves Under CECL		1,134
Transition Impact Gross		931
Impact of Deferred Taxes		(275)
Impact to Retained Earnings		656
Accounting Standards Update 2016-13 [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member] \| Real Estate Sector [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reserves Under Incurred Loss		11,698
Reserves Under CECL		21,540
Transition Impact Gross		9,842
Impact of Deferred Taxes		(2,910)
Impact to Retained Earnings		6,932
Accounting Standards Update 2016-13 [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member] \| Real Estate Sector [Member] \| 1-4 Family Residential Construction [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reserves Under Incurred Loss		135
Reserves Under CECL		28
Transition Impact Gross		(107)
Impact of Deferred Taxes		32
Impact to Retained Earnings		(75)
Accounting Standards Update 2016-13 [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member] \| Real Estate Sector [Member] \| Other construction/land [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reserves Under Incurred Loss		228
Reserves Under CECL		254
Transition Impact Gross		26
Impact of Deferred Taxes		(8)
Impact to Retained Earnings		18
Accounting Standards Update 2016-13 [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member] \| Real Estate Sector [Member] \| 1-4 Family - Closed-End [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reserves Under Incurred Loss		1,618
Reserves Under CECL		2,310
Transition Impact Gross		692
Impact of Deferred Taxes		(205)
Impact to Retained Earnings		487
Accounting Standards Update 2016-13 [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member] \| Real Estate Sector [Member] \| Equity Lines [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reserves Under Incurred Loss		290
Reserves Under CECL		210
Transition Impact Gross		(80)
Impact of Deferred Taxes		24
Impact to Retained Earnings		(56)
Accounting Standards Update 2016-13 [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member] \| Real Estate Sector [Member] \| Multi-Family Residential [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reserves Under Incurred Loss		274
Reserves Under CECL		574
Transition Impact Gross		300
Impact of Deferred Taxes		(89)
Impact to Retained Earnings		211
Accounting Standards Update 2016-13 [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member] \| Real Estate Sector [Member] \| Commercial Real Estate Owner Occupied [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reserves Under Incurred Loss		2,217
Reserves Under CECL		3,444
Transition Impact Gross		1,227
Impact of Deferred Taxes		(363)
Impact to Retained Earnings		864
Accounting Standards Update 2016-13 [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member] \| Real Estate Sector [Member] \| Commercial Real Estate Non Owner Occupied [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reserves Under Incurred Loss		6,199
Reserves Under CECL		14,380
Transition Impact Gross		8,181
Impact of Deferred Taxes		(2,418)
Impact to Retained Earnings		5,763
Accounting Standards Update 2016-13 [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member] \| Real Estate Sector [Member] \| Farmland [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reserves Under Incurred Loss		737
Reserves Under CECL		340
Transition Impact Gross		(397)
Impact of Deferred Taxes		117
Impact to Retained Earnings		(280)
Accounting Standards Update 2016-13 [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member] \| Agricultural Sector [Member] \| Agricultural Portfolio Segment [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reserves Under Incurred Loss		465
Reserves Under CECL		382
Transition Impact Gross		(83)
Impact of Deferred Taxes		25
Impact to Retained Earnings		(58)
Accounting Standards Update 2016-13 [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member] \| Commercial and Industrial Sector [Member] \| Commercial Portfolio Segment [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reserves Under Incurred Loss		1,060
Reserves Under CECL		1,418
Transition Impact Gross		358
Impact of Deferred Taxes		(106)
Impact to Retained Earnings		$ 252