Derivative Financial Instruments Derivative Financial Instruments (Narrative) (Details) $ in Thousands	12 Months Ended
Dec. 31, 2018 USD ($) contract
Derivative [Line Items]
Number of instruments held \| contract	3
Forward Contract effective July 18 2016 [Member]
Derivative [Line Items]
Derivative, notional amount	$ 40,000
Cash flow hedges, notional amount	$ 40,000
Swaption interest rate	2.98%
Term of contract	3 years
Forward Contract effective April 18 2016 [Member]
Derivative [Line Items]
Derivative, notional amount	$ 30,000
Cash flow hedges, notional amount	$ 30,000
Swaption interest rate	2.89%
Term of contract	4 years 6 months
Forward Contract effective October 18 2016 [Member]
Derivative [Line Items]
Derivative, notional amount	$ 40,000
Cash flow hedges, notional amount	$ 40,000
Swaption interest rate	2.841%
Term of contract	3 years
Fair Value Hedging [Member]
Derivative [Line Items]
Number of instruments held \| contract	2
Fair Value Hedging [Member] \| Commercial Real Estate [Member] \| Interest Rate Swap effective January 15 2015 [Member]
Derivative [Line Items]
Derivative, notional amount	$ 9,950
Swaption interest rate	4.33%
Term of contract	10 years
Fair Value Hedging [Member] \| Commercial Real Estate [Member] \| Interest Rate Swap effective December 18 2015 [Member]
Derivative [Line Items]
Derivative, notional amount	$ 11,300
Swaption interest rate	4.30%
Term of contract	10 years

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

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- Definition

Cash Flow Hedge Derivative Liability Notional Amount.

+ References

No definition available.

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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

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- Definition

The number of derivative instruments of a particular group held by the entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5579245-113959

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5580258-113959

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- Definition

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

+ References

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- Definition

Period the derivative contract is outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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