Represents the escalation rate assumed by the entity for an increase in labor, materials and equipment costs.

No definition available.

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- Definition

Represents the amount of estimated costs of decommissioning of nuclear facilities by the entity.

+ References

No definition available.

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- Definition

The carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Asset Retirement Obligation
-URI http://asc.fasb.org/extlink&oid=6505190

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- Definition

Amount of accretion expense recognized during the period that is associated with an asset retirement obligation. Accretion expense measures and incorporates changes due to the passage of time into the carrying amount of the liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)(3)
-URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6392676&loc=d3e7480-110848

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- Definition

Amount of asset retirement obligations settled, or otherwise disposed of, during the period. This may include asset retirement obligations transferred to third parties associated with the sale of a long-lived asset.

+ References

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- Definition

Amount of the Increase or Decrease in the amount of the asset retirement obligation during the current period for changes in the amount or timing of the estimated cash flows associated with the settlement of the obligation.

+ References

+ Details

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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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

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 210.5-02.12)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 12
-Article 5

+ Details

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Summary of significant accounting policies: Asset retirement obligations (Details) - USD ($)		12 Months Ended
	Apr. 17, 2015	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Asset Retirement Obligations
Balance at the beginning of the period		$ 432,260,000	$ 408,050,000
Liabilities settled		(299,000)	(406,000)
Accretion		26,108,000	24,616,000	$ 22,900,000
Change in Cash Flow Estimates	$ 49,084,000	144,161,000
Balance at the end of the period		$ 602,230,000	432,260,000	408,050,000
Assumed escalation rate for labor, material and equipment (as a percent)		2.50%
Fair value of external trust fund		$ 363,829,000	366,004,000
Hatch Unit No. 1
Asset Retirement Obligations
Estimated costs based on site study		258,000,000
Hatch Unit No. 1 \| Radiated structures
Asset Retirement Obligations
Estimated costs based on site study		193,000,000
Hatch Unit No. 1 \| Spent fuel management
Asset Retirement Obligations
Estimated costs based on site study		49,000,000
Hatch Unit No. 1 \| Non-radiated structures
Asset Retirement Obligations
Estimated costs based on site study		16,000,000
Hatch Unit No. 2
Asset Retirement Obligations
Estimated costs based on site study		282,000,000
Hatch Unit No. 2 \| Radiated structures
Asset Retirement Obligations
Estimated costs based on site study		213,000,000
Hatch Unit No. 2 \| Spent fuel management
Asset Retirement Obligations
Estimated costs based on site study		47,000,000
Hatch Unit No. 2 \| Non-radiated structures
Asset Retirement Obligations
Estimated costs based on site study		22,000,000
Vogtle Unit No. 1
Asset Retirement Obligations
Estimated costs based on site study		253,000,000
Vogtle Unit No. 1 \| Radiated structures
Asset Retirement Obligations
Estimated costs based on site study		178,000,000
Vogtle Unit No. 1 \| Spent fuel management
Asset Retirement Obligations
Estimated costs based on site study		49,000,000
Vogtle Unit No. 1 \| Non-radiated structures
Asset Retirement Obligations
Estimated costs based on site study		26,000,000
Vogtle Unit No. 2
Asset Retirement Obligations
Estimated costs based on site study		275,000,000
Vogtle Unit No. 2 \| Radiated structures
Asset Retirement Obligations
Estimated costs based on site study		195,000,000
Vogtle Unit No. 2 \| Spent fuel management
Asset Retirement Obligations
Estimated costs based on site study		47,000,000
Vogtle Unit No. 2 \| Non-radiated structures
Asset Retirement Obligations
Estimated costs based on site study		33,000,000
Nuclear
Asset Retirement Obligations
Balance at the beginning of the period		369,046,000	347,201,000
Accretion		23,231,000	21,845,000
Change in Cash Flow Estimates		96,181,000
Balance at the end of the period		488,458,000	369,046,000	347,201,000
Coal Ash Pond
Asset Retirement Obligations
Balance at the beginning of the period		42,609,000	40,760,000
Accretion		1,929,000	1,849,000
Change in Cash Flow Estimates		49,084,000
Balance at the end of the period		93,622,000	42,609,000	40,760,000
Other
Asset Retirement Obligations
Balance at the beginning of the period		20,605,000	20,089,000
Liabilities settled		(299,000)	(406,000)
Accretion		948,000	922,000
Change in Cash Flow Estimates		(1,104,000)
Balance at the end of the period		$ 20,150,000	$ 20,605,000	$ 20,089,000