Derivative Financial Instruments (Cash flow hedges) (Balance sheet category and fair values) (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Other liabilities \| Interest Rate Swap due March 17, 2021
Derivatives, Fair Value [Line Items]
Notional Amount, Other Liabilities	$ 25,000	$ 25,000
Fair Value, Other Liabilities	$ (346)	$ (447)
Receive Rate	1.321%	0.993%
Weighted Average Pay Rate	2.255%	2.255%
Other liabilities \| Interest Rate Swap due March 1, 2017
Derivatives, Fair Value [Line Items]
Notional Amount, Other Liabilities	$ 0	$ 20,000
Fair Value, Other Liabilities	$ 0	$ (114)
Receive Rate	0.00%	0.931%
Weighted Average Pay Rate	3.22%	3.22%
Other liabilities \| Interest Rate Swap due January 7, 2020
Derivatives, Fair Value [Line Items]
Notional Amount, Other Liabilities	$ 20,000	$ 20,000
Fair Value, Other Liabilities	$ (828)	$ (1,145)
Receive Rate	1.303%	0.868%
Weighted Average Pay Rate	3.355%	3.355%
Other liabilities \| Interest Rate Swap due March 26, 2019
Derivatives, Fair Value [Line Items]
Notional Amount, Other Liabilities	$ 10,000	$ 10,000
Fair Value, Other Liabilities	$ (6)	$ (42)
Receive Rate	1.329%	0.997%
Weighted Average Pay Rate	1.674%	1.674%
Other liabilities \| Interest Rate Swap due March 18, 2019
Derivatives, Fair Value [Line Items]
Notional Amount, Other Liabilities	$ 10,000	$ 10,000
Fair Value, Other Liabilities	$ (5)	$ (41)
Receive Rate	1.321%	0.993%
Weighted Average Pay Rate	1.658%	1.658%
Other liabilities \| Interest Rate Swap due June 15, 2024
Derivatives, Fair Value [Line Items]
Notional Amount, Other Liabilities	$ 20,000	$ 20,000
Fair Value, Other Liabilities	$ (393)	$ (214)
Receive Rate	1.32%	0.00%
Weighted Average Pay Rate	2.39%	2.39%
Other liabilities \| Interest Rate Swap due March 1, 2024
Derivatives, Fair Value [Line Items]
Notional Amount, Other Liabilities	$ 20,000	$ 20,000
Fair Value, Other Liabilities	$ (365)	$ (262)
Receive Rate	1.316%	0.00%
Weighted Average Pay Rate	2.352%	2.352%
Other assets \| Interest Rate Swap due May 10, 2021
Derivatives, Fair Value [Line Items]
Notional Amount, Other Assets	$ 35,667	$ 37,667
Fair Value, Other Assets	$ 557	$ 530
Receive Rate	3.735%	3.164%
Weighted Average Pay Rate	3.674%	3.674%

Interest Rate Cash Flow Hedge Derivative, Receive Rate, Percentage

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- Definition

Interest Rate Cash Flow Hedge Derivative, Weighted Average Pay Rate, Percentage

+ References

No definition available.

+ Details

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- Definition

Nominal or face amount used to calculate payments on the derivative asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5579245-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5580258-113959

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- Definition

Nominal or face amount used to calculate payments on the derivative liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5579245-113959

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Fair value as of the balance sheet date of interest rate derivative assets, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13433-108611

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- Definition

Fair value as of the balance sheet date of interest rate derivative liabilities, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as liabilities.

+ References

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