Interest Rate Swap Derivatives (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Notional Amount	$ 250,000	$ 250,000
Fair value	2,256	(692)
Other Assets [Member] \| Interest Rate Swap 1 [Member]
Notional Amount	75,000
Fair value	$ 598
Pay Rate	1.71%
Maturity	Mar. 31, 2020
Receive rate basis	1 month USD-LIBOR-BBA w/ -1 day lookback +10 basis points
Other Assets [Member] \| Interest Rate Swap 1 [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Spread on basis	0.10%
Other Assets [Member] \| Interest Rate Swap 2 [Member] \| Federal Funds Effective Swap Rate [Member]
Spread on basis	0.10%
Other Assets [Member] \| Interest Rate Swap 3 [Member]
Notional Amount	$ 75,000	75,000
Fair value	$ 837	$ 19
Pay Rate	1.92%	1.92%
Maturity	Mar. 31, 2022	Mar. 31, 2022
Receive rate basis	1 month USD-LIBOR-BBA w/ -1 day lookback +10 basis points	1 month USD-LIBOR-BBA w/ -1 day lookback +10 basis points
Other Assets [Member] \| Interest Rate Swap 3 [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Spread on basis	0.10%	0.10%
Other Liabilities [Member] \| Interest Rate Swap 1 [Member]
Notional Amount		$ 75,000
Fair value		$ (197)
Pay Rate		1.71%
Maturity		Mar. 31, 2020
Receive rate basis		1 month USD-LIBOR-BBA w/ -1 day lookback +10 basis points
Other Liabilities [Member] \| Interest Rate Swap 1 [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Spread on basis		0.10%
Other Liabilities [Member] \| Interest Rate Swap 2 [Member]
Notional Amount	$ 100,000	$ 100,000
Fair value	$ 821	$ (514)
Pay Rate	1.74%	1.74%
Maturity	Apr. 15, 2021	Apr. 15, 2021
Receive rate basis	Federal Funds Effective Rate +10 basis points	Federal Funds Effective Rate +10 basis points
Other Liabilities [Member] \| Interest Rate Swap 2 [Member] \| Federal Funds Effective Swap Rate [Member]
Spread on basis		0.10%

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

+ Details

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- Definition

The percentage points added to the reference rate to compute the variable rate on the interest rate derivative.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Fair value of the assets less the liabilities of a derivative or group of derivatives.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41271-113958

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958

Reference 3: 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

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13495-108611

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- Definition

Date the derivative contract matures, in CCYY-MM-DD format.

+ References

No definition available.

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- Definition

Fixed interest rate that will be received or paid upon exercise of the interest rate swaption contract.

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

Reference to the index or unit of measurement for the underlying which establishes the pricing terms of the derivative instrument. For example, the basis on the underlying for a natural gas futures contract might be the NYMEX price per million British thermal units (MMBtu).

+ References

No definition available.

+ Details

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