Financial Instruments and Investments [Line Items]

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- Definition

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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- Definition

Face (par) amount of debt instrument at time of issuance.

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- Definition

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

+ References

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- Definition

Decommission fund to pay for the costs of decontaminating and decommissioning of facilities through collection of revenues derived from utility assessments and government appropriations. Decommission fund investment for the process whereby a power station, at the end of its economic life, is taken permanently out of service and its site made available for other purposes. In the case of a nuclear station this comprises three different states of clearance. Immediately after the final closure, radioactive material such as nuclear fuel and operational waste is removed and the buildings surrounding the reactor shield are dismantled and finally the reactor itself is dismantled.

+ References

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- Definition

The estimated net amount of unrealized gains or losses on interest rate cash flow hedges as of the balance sheet date expected to be reclassified to earnings within the next twelve months.

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Financial Instruments And Investments (Long-Term Debt And Short-Term Borrowings - Narratives) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Jun. 28, 2018	Dec. 31, 2017	Aug. 18, 2010	May 01, 2005
Financial Instruments and Investments [Line Items]
Interest Rate Cash Flow Hedge Loss to be Reclassified During Next 12 Months, Net	$ 600
Decommissioning Fund Investments	276,905		$ 286,866
Nuclear Fuel Financing
Financial Instruments and Investments [Line Items]
Line of Credit Facility, Amount Outstanding	26,200		88,500
Working Capital and General Purpose
Financial Instruments and Investments [Line Items]
Line of Credit Facility, Amount Outstanding	23,000		85,000
Pollution Control Bonds
Financial Instruments and Investments [Line Items]
Debt Instrument, Face Amount	159,800
RGRT Senior Notes
Financial Instruments and Investments [Line Items]
Debt Instrument, Face Amount				$ 110,000
Long-term Debt, Gross	$ 110,000		$ 45,000
4.22% Senior Notes, due 2028 \| Senior Notes
Financial Instruments and Investments [Line Items]
Debt Instrument, Face Amount		$ 125,000
Debt Instrument, Interest Rate, Stated Percentage	4.22%	4.22%	4.22%
4.07% RGRT Senior Notes, due 2025 \| RGRT Senior Notes
Financial Instruments and Investments [Line Items]
Debt Instrument, Face Amount		$ 65,000
Debt Instrument, Interest Rate, Stated Percentage	4.07%	4.07%	4.07%
6.00% Senior Notes, Net of Discount, due 2035 \| Senior Notes
Financial Instruments and Investments [Line Items]
Debt Instrument, Face Amount					$ 400,000
Debt Instrument, Interest Rate, Stated Percentage	6.00%		6.00%		6.00%