Derivative Instruments (Summary Of Derivative Instruments) (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2018	Dec. 31, 2017
Derivative Instruments [Abstract]
Notional amount	$ 1,378	$ 2,185
Weighted average pay rate on interest-rate swaps	3.12%	3.75%
Weighted average receive rate on interest-rate swaps	2.20%	1.52%
Weighted average maturity (years)	2 years 2 months 12 days	2 years 1 month 6 days
Fair value of interest-rate swaps	$ (9)	$ (56)
Fair value of yield maintenance provisions	$ 9	$ 56

Derivative weighted average pay rate.

No definition available.

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- Definition

Derivative weighted average receive rate.

+ References

No definition available.

+ Details

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- Definition

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

+ References

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

Average remaining period until maturity of the derivative contract, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- References

No definition available.

+ Details

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- Definition

Net fair value as of the balance sheet date of the embedded derivative or group of embedded derivatives classified as assets, net of those classified as liabilities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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