Regulatory Matters (Schedule Of The Total Risk-based, Tier 1 Risk-based And Tier 1 Leverage Requirements) (Details) $ in Thousands	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2015
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Common Equity Tier 1 Risk-based Capital Ratio: Ratio	0.10
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: Ratio	0.06
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	0.1131	0.1182
Tier 1 Risk-based Capital Ratio: Ratio	0.1131	0.1182
Total Risk-based Capital Ratio: Ratio	0.1385	0.1445
Tier 1 Leverage Ratio: Ratio	0.0792	0.0901
Common Equity Tier 1 Risk-based Capital Ratio: Amount	$ 171,208	$ 164,060
Common Equity Tier 1 Risk-based Capital Ratio: Adequately Capitalized Minimum, Amount	68,095	62,463
Tier 1 Risk-based Capital Ratio: Amount	171,208	164,060
Tier 1 Risk-based Capital Ratio: Minimum to be Adequately Capitalized Amount	90,793	83,284
Total Risk-based Capital Ratio: Amount	209,603	200,589
Total Risk-based Capital Ratio: Minimum to be Adequately Capitalized Amount	121,057	111,046
Tier 1 Leverage Ratio: Amount	171,208	164,060
Tier 1 Leverage Ratio: Minimum to be Adequately Capitalized Amount	$ 86,449	$ 72,833
Bank [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Common Equity Tier 1 Risk-based Capital Ratio: Ratio	0.1171	0.1238
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	0.0650	0.0650
Tier 1 Risk-based Capital Ratio: Ratio	0.1171	0.1238
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	0.1296	0.1363
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	0.0820	0.0944
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	$ 179,837	$ 171,932
Common Equity Tier 1 Risk-based Capital Ratio: Adequately Capitalized Minimum, Amount	69,088	62,496
Common Equity Tier 1 Risk-based Capital Ratio: Well Capitalized Minimum, Amount	99,794	90,271
Tier 1 Risk-based Capital Ratio: Amount	179,837	171,932
Tier 1 Risk-based Capital Ratio: Minimum to be Adequately Capitalized Amount	92,117	83,327
Tier 1 Risk-based Capital Ratio: Minimum to be Well Capitalized Amount	122,823	111,103
Total Risk-based Capital Ratio: Amount	199,033	189,300
Total Risk-based Capital Ratio: Minimum to be Adequately Capitalized Amount	122,823	111,103
Total Risk-based Capital Ratio: Minimum to be Well Capitalized Amount	153,529	138,879
Tier 1 Leverage Ratio: Amount	179,837	171,932
Tier 1 Leverage Ratio: Minimum to be Adequately Capitalized Amount	87,715	72,871
Tier 1 Leverage Ratio: Minimum to be Well Capitalized Amount	$ 109,644	$ 91,088

Tangible Capital Required For Well Capitalized To Tangible Assets

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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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Amount of tangible capital as defined by regulatory framework.

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