Fair value of financial instruments - Additional Quantitative Information about Assets Measured at Fair Value on Nonrecurring Basis (Details) - Nonrecurring Basis - Level 3 - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Impaired Loans
Fair Value Inputs, Assets, Quantitative Information
Assets, Fair Value Estimate	$ 780	$ 2,884
Range and weighted average of appraisal adjustments	65.20%	28.20%
Range and weighted average of liquidation expenses	5.10%	5.50%
Impaired Loans \| Minimum
Fair Value Inputs, Assets, Quantitative Information
Range and weighted average of appraisal adjustments	6.40%	9.00%
Range and weighted average of liquidation expenses	3.00%	3.00%
Impaired Loans \| Maximum
Fair Value Inputs, Assets, Quantitative Information
Range and weighted average of appraisal adjustments	97.00%	97.00%
Range and weighted average of liquidation expenses	6.00%	6.00%
Other Real Estate Owned
Fair Value Inputs, Assets, Quantitative Information
Assets, Fair Value Estimate	$ 487	$ 527
Range and weighted average of appraisal adjustments	35.90%	29.90%
Range and weighted average of liquidation expenses	5.00%	5.00%
Other Real Estate Owned \| Minimum
Fair Value Inputs, Assets, Quantitative Information
Range and weighted average of appraisal adjustments	35.90%	3.10%
Range and weighted average of liquidation expenses	3.00%	3.00%
Other Real Estate Owned \| Maximum
Fair Value Inputs, Assets, Quantitative Information
Range and weighted average of appraisal adjustments	35.90%	58.10%
Range and weighted average of liquidation expenses	6.00%	6.00%

Represents the range and weighted average of appraisal adjustments presented as a percent of the appraisal.

No definition available.

Name:	pfis_RangeAndWeightedAverageOfAppraisalAdjustments
Namespace Prefix:	pfis_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Represents the range and weighted average of liquidation expenses presented as a percent of the appraisal.

+ References

No definition available.

+ Details

Name:	pfis_RangeAndWeightedAverageOfLiquidationExpenses
Namespace Prefix:	pfis_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258

+ Details

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

- Details

Name:	us-gaap_FairValueByMeasurementFrequencyAxis=us-gaap_FairValueMeasurementsNonrecurringMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FairValueByAssetClassAxis=pfis_ImpairedLoansMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel3Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FairValueByAssetClassAxis=pfis_OtherRealEstateOwnedMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: