Credit quality segments of loans receivable and the allowance for loan losses (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Financing Receivable, Past Due [Line Items]
Totals	$ 1,135,758	$ 1,066,750
Allowance For Loan And Lease Losses Collectively Evaluated Loans Credit Quality Segment [Member]
Financing Receivable, Past Due [Line Items]
Performing loans	1,134,514	1,046,614
Potential problem loans 1	6,768	25,016
Impaired loans
Unallocated allowance
Totals	1,141,282	1,071,630
Allowance For Loan And Lease Losses Collectively Evaluated Allowance Credit Quality Segment [Member]
Financing Receivable, Past Due [Line Items]
Performing loans	12,228	10,456
Potential problem loans 1	407	1,529
Impaired loans
Unallocated allowance	901	881
Totals	13,536	12,866
Allowance For Loan And Lease Losses Individually Evaluated Loans Credit Quality Segment [Member]
Financing Receivable, Past Due [Line Items]
Performing loans
Potential problem loans 1
Impaired loans	7,161	7,797
Unallocated allowance
Totals	7,161	7,797
Allowance For Loan And Lease Losses Individually Evaluated Allowance Credit Quality Segment [Member]
Financing Receivable, Past Due [Line Items]
Performing loans
Potential problem loans 1
Impaired loans	167	96
Unallocated allowance
Totals	167	96
Allowance For Loan And Lease Losses Total Portfolio Loans Credit Quality Segment [Member]
Financing Receivable, Past Due [Line Items]
Performing loans	1,134,514	1,046,614
Potential problem loans 1	6,768	25,016
Impaired loans	7,161	7,797
Unallocated allowance
Totals	1,148,443	1,079,427
Allowance For Loan And Lease Losses Total Portfolio Allowance Credit Quality Segment [Member]
Financing Receivable, Past Due [Line Items]
Performing loans	12,228	10,456
Potential problem loans 1	407	1,529
Impaired loans	167	96
Unallocated allowance	901	881
Totals	$ 13,703	$ 12,962

Amount of allowance for credit loss on receivable, classified as other and current.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(3)(a)(4))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

Name:	us-gaap_AllowanceForDoubtfulOtherReceivablesCurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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_FinancingReceivableRecordedInvestmentPastDueLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Reflects the carrying amount of loans deemed to be questionable as to collection on which interest is continuing to be earned or accrued.

+ References

No definition available.

+ Details

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

- Definition

Reflects the carrying amount of loans deemed to be questionable as to collection on which no interest is continuing to be recognized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=123577603&loc=d3e5111-111524

+ Details

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

- Definition

Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI https://asc.fasb.org/extlink&oid=124259787&loc=d3e4428-111522

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7)
-URI https://asc.fasb.org/extlink&oid=126897435&loc=d3e534808-122878

+ Details

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

- Definition

Amount of loan with fixed rate of interest.

+ References

+ Details

Name:	us-gaap_LoansReceivableWithFixedRatesOfInterest1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=SAL_AllowanceForLoanAndLeaseLossesCollectivelyEvaluatedLoansCreditQualitySegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=SAL_AllowanceForLoanAndLeaseLossesCollectivelyEvaluatedAllowanceCreditQualitySegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=SAL_AllowanceForLoanAndLeaseLossesIndividuallyEvaluatedLoansCreditQualitySegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=SAL_AllowanceForLoanAndLeaseLossesIndividuallyEvaluatedAllowanceCreditQualitySegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=SAL_AllowanceForLoanAndLeaseLossesTotalPortfolioLoansCreditQualitySegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=SAL_AllowanceForLoanAndLeaseLossesTotalPortfolioAllowanceCreditQualitySegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: