Loans and Allowance for Loan Losses, Troubled Debt Restructurings (Details) $ in Thousands	3 Months Ended
Mar. 31, 2018 USD ($) Loan Contract Property	Mar. 31, 2017 USD ($) Loan Property
Troubled Debt Restructurings [Abstract]
Number of TDR loans in the portfolio \| Loan	11	10
TDR loans in the portfolio	$ 5,200	$ 6,100
Number of TDR loans current and performing \| Loan	7	6
Number of TDRs with defaults occurring within 12 months of modification \| Loan	0	0
Commercial and Industrial [Member]
Troubled Debt Restructurings [Abstract]
Number of Contracts \| Contract	1
Pre-Modification Outstanding Recorded Investment	$ 191,000
Post-Modification Outstanding Recorded Investment	$ 191,000
Residential Real Estate [Member]
Troubled Debt Restructurings [Abstract]
Number of foreclosed properties in possession or in process of foreclosure \| Property	0	1
Recorded investment of foreclosed properties in possession or in process of foreclosure		$ 52

Number of foreclosed properties in possession or in the process of foreclosure.

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- Definition

The number of troubled debt restructuring loans outstanding in the portfolio.

+ References

No definition available.

+ Details

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- Definition

Represents the number of troubled debt restructuring loans that are current and performing in accordance with modified terms.

+ References

No definition available.

+ Details

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953676-111524

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- Definition

Post-modification amount of investment in financing receivables modified by troubled debt restructurings.

+ References

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- Definition

Pre-modification amount of investment in financing receivables modified by troubled debt restructurings.

+ References

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- Definition

The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=82895541&loc=d3e18845-111554

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953682-111524

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- Definition

Recorded investment of consumer mortgage loan receivables secured by residential real estate properties for which formal foreclosure proceedings are in process.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 35
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL49126937-111524

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- References

No definition available.

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