Asset Retirement Obligation, Reductions Due to Plant Sales

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- Definition

Number Of Coal Fired Power Plants

+ References

No definition available.

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- Definition

Number Of Generating Facilities

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No definition available.

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- Definition

Production Plan Capacity

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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.

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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.

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- Definition

Amount of increase (decrease) in the asset retirement obligation from changes in the amount or timing of the estimated cash flows associated with the settlement of the obligation.

+ 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)(4)
-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 35
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=6392603&loc=d3e7123-110846

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- Definition

Noncurrent portion of 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.

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- Definition

Amount of gain (loss) from the difference between the sale price or salvage price and the book value of an asset that was sold or retired, and gain (loss) from the write down of assets from their carrying value to fair value.

+ References

No definition available.

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- Definition

The period end amount owned by the reporting utility of a jointly owned utility plant in service.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 980
-SubTopic 360
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 10.C)
-URI http://asc.fasb.org/extlink&oid=6500719&loc=d3e659983-123033

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- Definition

The period end amount of construction work in progress at a jointly owned electricity generation plant.

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- Definition

The period end amount of accumulated depreciation in a jointly owned electricity generation plant.

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- Definition

The proportionate share of interest (percent) in a jointly owned utility plant.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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Property, Plant and Equipment (Details) $ in Millions	3 Months Ended
Property, Plant and Equipment (Details) $ in Millions	Mar. 31, 2018 USD ($) generating_facility power_plant MW	Mar. 31, 2017 USD ($)	Dec. 31, 2017 USD ($)
Property, Plant and Equipment [Line Items]
Asset Retirement Obligations, Noncurrent	$ 128.3		$ 131.2
Asset Retirement Obligation, Accretion Expense	0.7
Asset Retirement Obligation, Liabilities Settled	(0.2)
Asset Retirement Obligation, Reductions Due to Plant Sales	(3.4)
Gain (Loss) on Sale of Assets and Asset Impairment Charges	(0.6)	$ (19.4)
Electric Transmission [Member] \| Dpandl Investment [Member]
Property, Plant and Equipment [Line Items]
Jointly Owned Utility Plant, Ownership Amount of Construction Work in Progress	0.0
Jointly Owned Utility Plant, Gross Ownership Amount of Plant in Service	39.4
Jointly Owned Utility Plant, Ownership Amount of Plant Accumulated Depreciation	9.0
Total Jointly Owned Stations [Member] \| Dpandl Investment [Member]
Property, Plant and Equipment [Line Items]
Jointly Owned Utility Plant, Ownership Amount of Construction Work in Progress	2.3
Jointly Owned Utility Plant, Gross Ownership Amount of Plant in Service	51.3
Jointly Owned Utility Plant, Ownership Amount of Plant Accumulated Depreciation	$ 20.5
Total Jointly Owned Stations [Member] \| Dpandl Share [Member]
Property, Plant and Equipment [Line Items]
Production Plan Capacity \| MW	1,137
Conesville Unit Four [Member] \| Dpandl Investment [Member]
Property, Plant and Equipment [Line Items]
Jointly Owned Utility Plant, Ownership Amount of Construction Work in Progress	$ 2.3
Jointly Owned Utility Plant, Gross Ownership Amount of Plant in Service	0.6
Jointly Owned Utility Plant, Ownership Amount of Plant Accumulated Depreciation	$ 0.6
Conesville Unit Four [Member] \| Dpandl Share [Member]
Property, Plant and Equipment [Line Items]
Jointly Owned Utility Plant, Proportionate Ownership Share	16.50%
Killen Station [Member] \| Dpandl Investment [Member]
Property, Plant and Equipment [Line Items]
Jointly Owned Utility Plant, Ownership Amount of Construction Work in Progress	$ 0.0
Jointly Owned Utility Plant, Gross Ownership Amount of Plant in Service	9.5
Jointly Owned Utility Plant, Ownership Amount of Plant Accumulated Depreciation	$ 9.1
Killen Station [Member] \| Dpandl Share [Member]
Property, Plant and Equipment [Line Items]
Jointly Owned Utility Plant, Proportionate Ownership Share	67.00%
Stuart Station [Member] \| Dpandl Investment [Member]
Property, Plant and Equipment [Line Items]
Jointly Owned Utility Plant, Ownership Amount of Construction Work in Progress	$ 0.0
Jointly Owned Utility Plant, Gross Ownership Amount of Plant in Service	1.8
Jointly Owned Utility Plant, Ownership Amount of Plant Accumulated Depreciation	$ 1.8
Stuart Station [Member] \| Dpandl Share [Member]
Property, Plant and Equipment [Line Items]
Jointly Owned Utility Plant, Proportionate Ownership Share	35.00%
Subsidiaries [Member]
Property, Plant and Equipment [Line Items]
Number Of Coal Fired Power Plants \| power_plant	3
Asset Retirement Obligation	$ 4.7		$ 8.0
Asset Retirement Obligation, Revision of Estimate	$ 0.1
Number Of Generating Facilities \| generating_facility	3
Asset Retirement Obligation, Reductions Due to Plant Sales	$ (3.4)
Gain (Loss) on Sale of Assets and Asset Impairment Charges	$ 0.0	$ (19.4)
Subsidiaries [Member] \| Conesville Unit Four [Member] \| Dpandl Share [Member]
Property, Plant and Equipment [Line Items]
Production Plan Capacity \| MW	129
Subsidiaries [Member] \| Killen Station [Member] \| Dpandl Share [Member]
Property, Plant and Equipment [Line Items]
Production Plan Capacity \| MW	402
Subsidiaries [Member] \| Stuart Station [Member] \| Dpandl Share [Member]
Property, Plant and Equipment [Line Items]
Production Plan Capacity \| MW	606