Amount of amortization expense attributable to debt issuance costs.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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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.

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Significant Accounting Policies (Deferred Financing Costs) (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Aug. 03, 2018	Mar. 09, 2018
Amortization of deferred financing costs	$ 200	$ 300	$ 300
Unamortized debt issuance expense	1,400	1,600
Deferred financing costs	$ 1,376	$ 1,603
First Amended and Restated Revolving Credit, Term Loan and Security Agreement [Member]
Deferred financing costs				$ 400
New Markets Tax Credit (NMTC) Program [Member]
Deferred financing costs					$ 700