Regulatory Matters (Schedule Of The Total Risk-based, Tier 1 Risk-based And Tier 1 Leverage Requirements) (Details) $ in Thousands	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2015
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Common Equity Tier 1 Risk-based Capital Ratio: Well Capitalized Minimum: Ratio	0.065%
Tier 1 Risk-based Capital Ratio: Well Capitalized Minimum: Ratio	0.08		0.06
Total Risk-based Capital Ratio: Well Capitalized Minimum: Ratio	0.10
Tier 1 Leverage Ratio: Well Capitalized Minimum: Ratio	0.05
Franklin Financial Services Corporation [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Common Equity Tier 1 Risk-based Capital Ratio: Ratio	0.1520	0.1432
Tier 1 Risk-based Capital Ratio: Ratio	0.1520	0.1432
Total Risk-based Capital Ratio: Ratio	0.1841	0.1769
Tier 1 Leverage Ratio: Ratio	0.0852	0.0869
Common Equity Tier 1 Risk-based Capital Ratio: Amount	$ 148,365	$ 132,970
Common Equity Tier 1 Risk-based Capital Ratio: Adequately Capitalized Minimum, Amount	43,927	41,788
Tier 1 Risk-based Capital Ratio: Amount	148,365	132,970
Tier 1 Risk-based Capital Ratio: Minimum to be Adequately Capitalized Amount	58,569	55,717
Total Risk-based Capital Ratio: Amount	179,701	164,230
Total Risk-based Capital Ratio: Minimum to be Adequately Capitalized Amount	78,092	74,289
Tier 1 Leverage Ratio: Amount	148,365	132,970
Tier 1 Leverage Ratio: Minimum to be Adequately Capitalized Amount	$ 69,649	$ 61,191
Bank [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Common Equity Tier 1 Risk-based Capital Ratio: Ratio	0.1528	0.1407
Common Equity Tier 1 Risk-based Capital Ratio: Adequately Capitalized Minimum: Ratio	0.0450	0.0450
Common Equity Tier 1 Risk-based Capital Ratio: Well Capitalized Minimum: Ratio	0.065%	0.065%
Tier 1 Risk-based Capital Ratio: Ratio	0.1528	0.1407
Tier 1 Risk-based Capital Ratio: Adequately Capitalized Minimum: Ratio	0.0600	0.0600
Tier 1 Risk-based Capital Ratio: Well Capitalized Minimum: Ratio	0.0800	0.0800
Total Risk-based Capital Ratio: Ratio	0.1654	0.1533
Total Risk-based Capital Ratio: Adequately Capitalized Minimum: Ratio	0.0800	0.0800
Total Risk-based Capital Ratio: Well Capitalized Minimum: Ratio	0.1000	0.1000
Tier 1 Leverage Ratio: Ratio	0.0857	0.0854
Tier 1 Leverage Ratio: Adequately Capitalized Minimum: Ratio	0.0400	0.0400
Tier 1 Leverage Ratio: Well Capitalized Minimum: Ratio	0.0500	0.0500
Common Equity Tier 1 Risk-based Capital Ratio: Amount	$ 149,087	$ 130,678
Common Equity Tier 1 Risk-based Capital Ratio: Adequately Capitalized Minimum, Amount	43,901	41,809
Common Equity Tier 1 Risk-based Capital Ratio: Well Capitalized Minimum, Amount	63,413	60,390
Tier 1 Risk-based Capital Ratio: Amount	149,087	130,678
Tier 1 Risk-based Capital Ratio: Minimum to be Adequately Capitalized Amount	58,535	55,745
Tier 1 Risk-based Capital Ratio: Minimum to be Well Capitalized Amount	78,046	74,326
Total Risk-based Capital Ratio: Amount	161,335	142,384
Total Risk-based Capital Ratio: Minimum to be Adequately Capitalized Amount	78,046	74,326
Total Risk-based Capital Ratio: Minimum to be Well Capitalized Amount	97,558	92,908
Tier 1 Leverage Ratio: Amount	149,087	130,678
Tier 1 Leverage Ratio: Minimum to be Adequately Capitalized Amount	69,608	61,222
Tier 1 Leverage Ratio: Minimum to be Well Capitalized Amount	$ 87,009	$ 76,527

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Amount of total capital as defined by regulatory framework.

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Amount of minimum total risk-based capital required for capital adequacy as defined by regulatory framework.

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-Publisher FASB
-Name Accounting Standards Codification
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Amount of tangible capital as defined by regulatory framework.

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