Fair Value Measurements (Narrative) (Details)	9 Months Ended	12 Months Ended
Sep. 30, 2015 USD ($) impaired_loan	Dec. 31, 2014 USD ($) impaired_loan
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Number of impaired loans \| impaired_loan	8	9
Allowance related to impaired loans	$ 5,277,000	$ 5,643,000
Inventories [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans, collateral, discount rate	50.00%
Accounts Receivable [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans, collateral, discount rate	20.00%
Foreclosed [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans, collateral, discount rate	15.00%
Minimum [Member] \| Real Estate [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans, collateral, discount rate	20.00%	10.00%
Minimum [Member] \| Equipment [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans, collateral, discount rate	30.00%
Maximum [Member] \| Real Estate [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans, collateral, discount rate	25.00%	35.00%
Maximum [Member] \| Equipment [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans, collateral, discount rate	50.00%
Weighted average [Member] \| Real Estate [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans, collateral, discount rate	21.00%	20.00%
Fair value measurements, nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans with specific allocation	$ 4,564,000	$ 3,882,000
Allowance related to impaired loans	5,300,000	5,600,000
Impaired loans net of partial charge-offs	3,477,000	5,263,000
Impaired loans, financial assets, fair value, charge-offs	1,300,000	2,400,000
Foreclosed assets, net of valuation allowance	170,000	$ 0
Foreclosed assets, valuation allowance	$ 80,000

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Amount of allowance for credit losses related to recorded investment.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (a)(3)

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+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.10(4))

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