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Number of Requests For Proposal

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Public Utilities, Amendment to Requested Rate Increase (Decrease), Amount

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Public Utilities, Approved Rate Recovery Period

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Public Utilities, Approved Settlement, Additional Operating Expenses

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Public Utilities, Long-term Improvement Plan, Recovery Period

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Regulatory matters.

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Utilities Operating Expense, Expected Under-recovered Balance, Next 12 Months

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Carrying amount as of the balance sheet date of capitalized storm costs of a regulated entity that are expected to be recoverable through rate adjustments after one year or beyond the normal operating cycle, if longer.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 980
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The estimated maximum amount of possible loss from the contingency.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 4
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Amount of public utility's approved rate increase (decrease) by regulatory agency.

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Amount of public utility's requested rate increase (decrease) with regulatory agency.

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Percentage of public utility's requested rate increase (decrease) with regulatory agency.

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Regulatory Matters - Pennsylvania and West Virginia (Details)											6 Months Ended	10 Months Ended	12 Months Ended
	Dec. 22, 2015 USD ($)	Dec. 21, 2015 USD ($)	Nov. 03, 2015 proposal	Oct. 19, 2015 USD ($)	Sep. 10, 2015 USD ($)	Aug. 31, 2015 USD ($)	Aug. 14, 2015 USD ($)	Jun. 19, 2015	Apr. 09, 2015 USD ($)	Feb. 03, 2015 USD ($)	Jun. 30, 2015 USD ($)	Feb. 24, 2015 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($) proposal	Nov. 05, 2015 USD ($)
Pennsylvania
Regulatory Matters [Line Items]
Number of requests for proposal \| proposal			1,000,000											1
Project term			2 years											2 years
Requested rate increase (decrease)									$ 292,800,000
Approved additional operating expenses									87,700,000
Pennsylvania \| 3 Month Period
Regulatory Matters [Line Items]
Energy contract term														3 months
Pennsylvania \| 12 Month Period
Regulatory Matters [Line Items]
Energy contract term			12 months											12 months
Pennsylvania \| 24 Month Period
Regulatory Matters [Line Items]
Energy contract term			24 months											24 months
Pennsylvania \| Unfavorable Regulatory Action
Regulatory Matters [Line Items]
Statutory penalty, maximum														$ 234,000,000
Pennsylvania \| ME
Regulatory Matters [Line Items]
Requested rate increase (decrease)									89,300,000
Pennsylvania \| Penn
Regulatory Matters [Line Items]
Requested rate increase (decrease)									15,900,000
Pennsylvania \| WP
Regulatory Matters [Line Items]
Requested rate increase (decrease)									96,800,000
Pennsylvania \| PN
Regulatory Matters [Line Items]
Requested rate increase (decrease)									$ 90,800,000
Pennsylvania \| Pennsylvania Companies \| Unfavorable Regulatory Action
Regulatory Matters [Line Items]
Statutory penalty, maximum															$ 230,000,000
Minimum range of possible loss															$ 200,000,000
Pennsylvania \| PPUC \| ME
Regulatory Matters [Line Items]
Proposed ROE								1.80%
Energy consumption reduction targets (percent)								4.00%
Requested rate increase (decrease)				$ 43,440,000
Pennsylvania \| PPUC \| Penn
Regulatory Matters [Line Items]
Proposed ROE								1.70%
Energy consumption reduction targets (percent)								3.30%
Requested rate increase (decrease)				$ 56,350,000
Pennsylvania \| PPUC \| WP
Regulatory Matters [Line Items]
Proposed ROE								1.80%
Energy consumption reduction targets (percent)								2.60%
LTIP recovery period				5 years
Requested rate increase (decrease)				$ 88,340,000
Pennsylvania \| PPUC \| PN
Regulatory Matters [Line Items]
Proposed ROE								0.00%
Energy consumption reduction targets (percent)								3.90%
Requested rate increase (decrease)				$ 56,740,000
West Virginia \| MP and PE
Regulatory Matters [Line Items]
Requested rate increase (decrease)							$ 165,100,000
Requested rate increase (decrease) (percent)							12.50%
Under-recovered balance											$ 97,000,000
Under-recovered balance for 2016														23,700,000
West Virginia \| WVPSC \| MP and PE
Regulatory Matters [Line Items]
Requested rate increase (decrease)										$ 15,000,000
Cost recovery period										5 years
Deferred storm and property reserve deficiency										$ 46,000,000
West Virginia \| WVPSC \| MP and PE \| ENEC
Regulatory Matters [Line Items]
Requested rate increase (decrease)					$ 144,500,000
Settlement amount	$ 96,900,000
Amendment to requested rate increase (decrease)					$ (20,600,000)
West Virginia \| WVPSC \| MP and PE \| Vegetation Management Program Surcharge
Regulatory Matters [Line Items]
Requested rate increase (decrease)						$ 37,700,000					$ 2,100,000	$ 49,900,000
Settlement amount		$ 36,700,000
Requested rate increase (decrease) (percent)						2.80%
Approved rate recovery period		2 years
West Virginia \| WVPSC \| MP and PE \| Vegetation Management Program Surcharge \| Scenario, Forecast
Regulatory Matters [Line Items]
Requested rate increase (decrease)													$ 23,900,000
West Virginia \| WVPSC \| MP and PE \| Harrison Power Station \| ENEC
Regulatory Matters [Line Items]
Requested rate increase (decrease)														$ 44,400,000