Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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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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Long-Term Debt - Schedule of Long-Term Debt (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2021	Dec. 31, 2020	Sep. 28, 2020
Debt Instrument [Line Items]
Unamortized debt issuance expense	$ (1,051)	$ (1,154)
Long-term debt	123,949	123,846
5.50% Senior Secured Notes
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 125,000	$ 125,000
6.75% Senior Secured Notes [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross			$ 150,000
Senior Secured Notes \| 5.50% Senior Secured Notes
Debt Instrument [Line Items]
Maturity Date	Oct. 01, 2025