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Financial Instruments with Off-Balance Sheet Risk (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Lines of credit and standby letters of credit, unused
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loan commitments and standby letters of credit, off-balance sheet	$ 376,600	$ 349,300
Percentage of commitments expiring in 2016	42.00%
Percentage of commitments expiring between 2017 and 2023	41.00%
Percentage of commitments expiring 2024 and thereafter	17.00%
Lines of credit and standby letters of credit, unused | Interest Payable and Other Liabilities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Allowance for off-balance sheet commitments	$ 749	1,000
Commercial lines of credit
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loan commitments and standby letters of credit, off-balance sheet	191,300	173,300
Revolving home equity lines
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loan commitments and standby letters of credit, off-balance sheet	130,400	115,600
Undisbursed construction loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loan commitments and standby letters of credit, off-balance sheet	39,400	46,700
Personal and other lines of credit
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loan commitments and standby letters of credit, off-balance sheet	11,100	11,600
Standby letters of credit
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loan commitments and standby letters of credit, off-balance sheet	$ 4,400	$ 2,100

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- Definition

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- Definition

Loan Commitments And Standby Letters Of Credit, Percentage Expiring, After Year Eight

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- Definition

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Loan Commitments And Standby Letters of Credit, Percentage Expiring In Year Two Through Eight

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