Loans Receivable and Allowance for Loan Losses (Composition of Loans Receivable) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014	Dec. 31, 2013
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross	$ 519,349	$ 501,534
Deferred fees (net)	(388)	(399)
Total loans receivable	518,961	501,135
Allowance for loan losses	(6,007)	(5,875)	(5,727)	(5,708)
Net loans receivable	512,954	495,260
Percent of Loans	100.00%nwfl_PercentOfLoans	100.00%nwfl_PercentOfLoans
Residential Real Estate Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross	157,707	158,139
Allowance for loan losses	(1,353)	(1,323)	(1,332)	(1,441)
Percent of Loans	30.40%	31.50%
Commercial Real Estate Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross	265,635	261,956
Allowance for loan losses	(3,994)	(3,890)	(3,842)	(3,025)
Percent of Loans	51.10%	52.20%
Construction Real Estate Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross	20,180	19,221
Allowance for loan losses	(115)	(222)	(231)	(898)
Percent of Loans	3.90%	3.90%
Commercial, financial and agricultural [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross	55,353	42,514
Allowance for loan losses	(353)	(256)	(184)	(184)
Percent of Loans	10.70%	8.50%
Consumer loans to individuals [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross	20,474	19,704
Allowance for loan losses	$ (192)	$ (184)	$ (138)	$ (160)
Percent of Loans	3.90%	3.90%

Percent of Loans

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A valuation allowance for financing receivables that are expected to be uncollectible.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

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Amount of deferred interest and fee income, unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of acquired loans. Excludes amounts for loans and leases covered under loss sharing agreements.

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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