Derivative Financial Instruments (Cash flow hedges) (Balance sheet category and fair values) (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Other assets \| Interest Rate Swap due March 17, 2021
Derivatives, Fair Value [Line Items]
Notional Amount, Other Assets	$ 25,000
Fair Value, Other Assets	$ 239
Receive Rate	2.178%
Weighted Average Pay Rate	2.255%
Other assets \| Interest Rate Swap due March 26, 2019
Derivatives, Fair Value [Line Items]
Notional Amount, Other Assets	$ 10,000	$ 10,000
Fair Value, Other Assets	$ 69	$ 30
Receive Rate	2.286%	1.329%
Weighted Average Pay Rate	1.674%	1.674%
Other assets \| Interest Rate Swap due March 18, 2019
Derivatives, Fair Value [Line Items]
Notional Amount, Other Assets	$ 10,000	$ 10,000
Fair Value, Other Assets	$ 68	$ 29
Receive Rate	2.178%	1.60%
Weighted Average Pay Rate	1.658%	1.658%
Other assets \| Interest Rate Swap due May 10, 2021
Derivatives, Fair Value [Line Items]
Notional Amount, Other Assets	$ 32,667	$ 33,667
Fair Value, Other Assets	$ 1,010	$ 759
Receive Rate	4.24%	3.932%
Weighted Average Pay Rate	3.674%	3.674%
Other assets \| Interest Rate Swap due June 15, 2024
Derivatives, Fair Value [Line Items]
Notional Amount, Other Assets	$ 20,000
Fair Value, Other Assets	$ 316
Receive Rate	2.125%
Weighted Average Pay Rate	2.39%
Other assets \| Interest Rate Swap due March 1, 2024
Derivatives, Fair Value [Line Items]
Notional Amount, Other Assets	$ 20,000
Fair Value, Other Assets	$ 339
Receive Rate	2.006%
Weighted Average Pay Rate	2.352%
Other liabilities \| Interest Rate Swap due March 17, 2021
Derivatives, Fair Value [Line Items]
Notional Amount, Other Liabilities		$ 25,000
Fair Value, Other Liabilities		$ (106)
Receive Rate		1.60%
Weighted Average Pay Rate		2.255%
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	$ (380)	$ (621)
Receive Rate	1.704%	1.35%
Weighted Average Pay Rate	3.355%	3.355%
Other liabilities \| Interest Rate Swap due June 15, 2024
Derivatives, Fair Value [Line Items]
Notional Amount, Other Liabilities		$ 20,000
Fair Value, Other Liabilities		$ (177)
Receive Rate		1.588%
Weighted Average Pay Rate		2.39%
Other liabilities \| Interest Rate Swap due March 1, 2024
Derivatives, Fair Value [Line Items]
Notional Amount, Other Liabilities		$ 20,000
Fair Value, Other Liabilities		$ (149)
Receive Rate		1.481%
Weighted Average Pay Rate		2.352%

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

+ Details

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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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