Loans Receivable and Allowance for Loan Losses (Composition of Loans Receivable) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross	$ 501,534	$ 503,577
Deferred fees (net)	(399)	(480)
Total loans receivable	501,135	503,097
Allowance for loan losses	(5,875)	(5,708)	(5,502)	(5,458)
Net loans receivable	495,260	497,389
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	158,139	158,842
Allowance for loan losses	(1,323)	(1,441)	(1,797)
Percent of Loans	31.50%	31.60%
Commercial Real Estate Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross	261,956	273,144
Allowance for loan losses	(3,890)	(3,025)	(3,183)
Percent of Loans	52.20%	54.20%
Construction Real Estate Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross	19,221	20,551
Allowance for loan losses	(222)	(898)	(119)
Percent of Loans	3.90%	4.10%
Commercial Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross	42,514	35,745
Allowance for loan losses	(256)	(184)	(223)
Percent of Loans	8.50%	7.10%
Consumer Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross	19,704	15,295
Allowance for loan losses	$ (184)	$ (160)	$ (180)
Percent of Loans	3.90%	3.00%

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

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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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