Capital Ratios (Schedule Of The Total Risk-based, Tier 1 Risk-based And Tier 1 Leverage Requirements) (Details)	Mar. 31, 2023	Dec. 31, 2022
Franklin Financial Services Corporation [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Common Equity Tier 1 Risk-based Capital Ratio: Ratio	0.1424	0.1422
Tier 1 Risk-based Capital Ratio: Ratio	0.1424	0.1422
Total Risk-based Capital Ratio: Ratio	0.1721	0.1721
Tier 1 Leverage Ratio: Ratio	0.0958	0.0895
Bank [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Common Equity Tier 1 Risk-based Capital Ratio: Ratio	0.1474	0.1463
Common Equity Tier 1 Risk-based Capital Ratio: Adequately Capitalized Minimum: Ratio	0.0450
Common Equity Tier 1 Risk-based Capital Ratio: Well Capitalized Minimum: Ratio	0.065
Tier 1 Risk-based Capital Ratio: Ratio	0.1474	0.1463
Tier 1 Risk-based Capital Ratio: Adequately Capitalized Minimum: Ratio	0.0600
Tier 1 Risk-based Capital Ratio: Well Capitalized Minimum: Ratio	0.08
Total Risk-based Capital Ratio: Ratio	0.1599	0.1588
Total Risk-based Capital Ratio: Adequately Capitalized Minimum: Ratio	0.0800
Total Risk-based Capital Ratio: Well Capitalized Minimum: Ratio	0.10
Tier 1 Leverage Ratio: Ratio	0.0992	0.0921
Tier 1 Leverage Ratio: Adequately Capitalized Minimum: Ratio	0.0400
Tier 1 Leverage Ratio: Well Capitalized Minimum: Ratio	0.05

Tangible Capital Required For Well Capitalized To Tangible Assets

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Ratio of minimum total risk-based capital to risk-weighted assets required for capital adequacy as defined by regulatory framework.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1B
-URI https://asc.fasb.org/extlink&oid=117337116&loc=SL5958570-112826

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Ratio of minimum tangible capital to tangible assets required for capital adequacy as defined by regulatory framework.

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