Financial Instruments and Investments [Line Items]

No definition available.

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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.

+ 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))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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- Definition

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

+ References

+ Details

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=35736893&loc=d3e80748-113994

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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.

+ References

+ Details

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- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

No definition available.

+ Details

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- Definition

The cash outflow from settlement of a long-term debt security issued by a state, certain agencies or authorities, a local government, or development corporation to finance the construction of air- or water-pollution control facilities or sewage or solid waste disposal facilities pursuant to federal law. The bonds are backed by the credit of the beneficiary of the financing rather than the credit of the issuer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3291-108585

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Financial Instruments And Investments (Long-Term Debt And Short-Term Borrowings - Narratives) (Details) - USD ($) $ in Thousands	1 Months Ended		12 Months Ended
	Sep. 30, 2017	Aug. 31, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Aug. 15, 2017	Aug. 28, 2012	May 01, 2005
Financial Instruments and Investments [Line Items]
Repayments of Pollution Control Bond			$ 33,300	$ 0	$ 0
Repayments of Debt			50,000	0	$ 15,000
Interest Rate Cash Flow Hedge Loss to be Reclassified During Next 12 Months, Net			600
Decommissioning Fund Investments			286,866	255,708
1.875% 2012 Series A Refunding Bonds, due 2032
Financial Instruments and Investments [Line Items]
Repayments of Pollution Control Bond	$ 33,300
Nuclear Fuel Financing
Financial Instruments and Investments [Line Items]
Line of Credit Facility, Amount Outstanding			88,500	37,600
Working Capital and General Purpose
Financial Instruments and Investments [Line Items]
Line of Credit Facility, Amount Outstanding			$ 85,000	$ 44,000
Pollution Control Bonds \| 1.875% 2012 Series A Refunding Bonds, due 2032
Financial Instruments and Investments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	1.875%		1.875%	1.875%			1.875%
Senior Notes \| 6.00% Senior Notes, Net of Discount, due 2035
Financial Instruments and Investments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			6.00%	6.00%				6.00%
RGRT Senior Notes
Financial Instruments and Investments [Line Items]
Long-term Debt, Gross			$ 45,000	$ 95,000
RGRT Senior Notes \| 4.47% Senior Notes, Series B, due 2017
Financial Instruments and Investments [Line Items]
Repayments of Debt		$ 50,000
Debt Instrument, Interest Rate, Stated Percentage		4.47%	4.47%	4.47%		4.47%