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Credit Facility (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Line of Credit Facility [Line Items]
Debt Instrument, Face Amount	$ 50,000
Debt Instrument, Covenant, Minimum Liquidity	50,000
Unamortized Debt Issuance Expense	$ 145	$ 185
Minimum [Member] | LIBOR Rate [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	1.50%
Minimum [Member] | Federal Funds Rate [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	1.50%
Maximum [Member] | LIBOR Rate [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	2.25%
Maximum [Member] | Federal Funds Rate [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	2.25%

X

- Definition

Debt Instrument, Covenant, Minimum Liquidity

+ References

No definition available.

+ Details

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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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

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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X

- Definition

The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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