Debt Instrument, Redemption Period

No definition available.

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Namespace Prefix:	fraf_
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Balance Type:	na
Period Type:	duration

- Definition

Amount of short-term and long-term debt and lease obligation.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1

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-SubTopic 210
-Name Accounting Standards Codification
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22)(a)(1))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1B

+ Details

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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 835
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482925/835-30-45-2

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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482900/835-30-50-1

+ Details

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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

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

- Definition

Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-SubTopic 10
-Topic 210
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16)(a)(2))
-Publisher FASB
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

Name:	us-gaap_DebtInstrumentRedemptionPeriodAxis=fraf_MaturingSeptember12030Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentRedemptionPeriodAxis=fraf_MaturingSeptember12035Member
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- Details

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- Details

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- Details

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Balance Type:
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- Details

Name:	us-gaap_DebtInstrumentRedemptionPeriodAxis=fraf_DebtInstrumentRedemptionPeriodSixMember
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- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_SubordinatedDebtMember
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Subordinate Notes (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Sep. 30, 2025	Dec. 31, 2024
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Debt issuance costs	$ 155
Redemption period	5 years
Maturing September 1, 2030 [Member]
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Subordinate notes	$ 6,000	$ 15,000
Maturing September 1, 2035 [Member]
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Subordinate notes	5,000
Through June 29, 2025 [Member]
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Subordinate notes	$ 6,000
Basis spread on variable rate	4.93%
Through September 1, 2025 [Member]
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Interest rate	4.93%
Through June 29, 2030 [Member]
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Subordinate notes	$ 5,000
Interest rate	5.25%
After June 29, 2030 [Member]
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Interest rate	5.25%
Basis spread on variable rate	4.92%
Subordinated Notes [Member]
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Debt	$ 10,845		$ 19,699
Subordinate notes	$ 11,000	$ 9,000