Financial Derivatives (Schedule Of Interest Rate Swap) (Details) (Interest Rate Swap Maturing [Member], USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015
Interest Rate Swap Maturing [Member]
Derivative [Line Items]
Notional Amount	$ 10,000
Maturity Date	May 30, 2015
Fixed Interest Rate	3.87%
Variable Interest Rate	0.02%
Amount Expected to be Expensed into Earnings within the next 12 Months	$ 64

Amount Expected To Be Expensed Into Earnings Within The Next Twelve Months

No definition available.

Name:	fraf_AmountExpectedToBeExpensedIntoEarningsWithinNextTwelveMonths
Namespace Prefix:	fraf_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 12

-Section 13

-Sentence Column B

+ Details

Name:	invest_DerivativeNotionalAmount
Namespace Prefix:	invest_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	instant

- Definition

Fixed interest rate related to the interest rate derivative.

+ References

No definition available.

+ Details

Name:	us-gaap_DerivativeFixedInterestRate
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Details

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

- Definition

Date the derivative contract matures, in CCYY-MM-DD format.

+ References

No definition available.

+ Details

Name:	us-gaap_DerivativeMaturityDates
Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Variable interest rate in effect as of the balance sheet date related to the interest rate derivative.

+ References

No definition available.

+ Details

Name:	us-gaap_DerivativeVariableInterestRate
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant