Regulatory Matters (Schedule Of The Total Risk-based, Tier 1 Risk-based And Tier 1 Leverage Requirements) (Details) $ in Thousands	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	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	0.1182	0.1422
Tier 1 Risk-based Capital Ratio: Ratio	0.1182	0.1422
Total Risk-based Capital Ratio: Ratio	0.1445	0.1721
Tier 1 Leverage Ratio: Ratio	0.0901	0.0895
Common Equity Tier 1 Risk-based Capital Ratio: Amount	$ 164,060	$ 156,468
Common Equity Tier 1 Risk-based Capital Ratio: Adequately Capitalized Minimum, Amount	62,463	49,529
Tier 1 Risk-based Capital Ratio: Amount	164,060	156,468
Tier 1 Risk-based Capital Ratio: Minimum to be Adequately Capitalized Amount	83,284	66,039
Total Risk-based Capital Ratio: Amount	200,589	189,370
Total Risk-based Capital Ratio: Minimum to be Adequately Capitalized Amount	111,046	88,051
Tier 1 Leverage Ratio: Amount	164,060	156,468
Tier 1 Leverage Ratio: Minimum to be Adequately Capitalized Amount	$ 72,833	$ 69,937
Bank [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Common Equity Tier 1 Risk-based Capital Ratio: Ratio	0.1238	0.1463
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	0.1238	0.1463
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	0.1363	0.1588
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	0.0944	0.0921
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	$ 171,932	$ 160,975
Common Equity Tier 1 Risk-based Capital Ratio: Adequately Capitalized Minimum, Amount	62,496	49,523
Common Equity Tier 1 Risk-based Capital Ratio: Well Capitalized Minimum, Amount	90,271	71,533
Tier 1 Risk-based Capital Ratio: Amount	171,932	160,975
Tier 1 Risk-based Capital Ratio: Minimum to be Adequately Capitalized Amount	83,327	66,030
Tier 1 Risk-based Capital Ratio: Minimum to be Well Capitalized Amount	111,103	88,041
Total Risk-based Capital Ratio: Amount	189,300	174,754
Total Risk-based Capital Ratio: Minimum to be Adequately Capitalized Amount	111,103	88,041
Total Risk-based Capital Ratio: Minimum to be Well Capitalized Amount	138,879	110,051
Tier 1 Leverage Ratio: Amount	171,932	160,975
Tier 1 Leverage Ratio: Minimum to be Adequately Capitalized Amount	72,871	69,928
Tier 1 Leverage Ratio: Minimum to be Well Capitalized Amount	$ 91,088	$ 87,411

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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