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Net Book Value and related ARO's of Assets Sold

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- Definition

Proceeds Due at Closing

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- Definition

Regulatory Assets and Liabilities [Line Items]

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- Definition

The yearly expense to be charged against earnings to allocate the capitalized costs of the deferred nuclear generating units regulatory asset.

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Amount of consideration received or receivable for the disposal of assets and liabilities, including discontinued operation.

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- Definition

Amount of cash inflow for the sale of long-lived, physical assets used to produce goods and services and not intended for resale, classified as other.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
-URI http://asc.fasb.org/extlink&oid=6516133

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- Definition

The amount for the individual regulatory asset as itemized in a table of regulatory assets as of the end of the period.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 980
-SubTopic 340
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6499975&loc=d3e44250-110382

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Carrying amount as of the balance sheet date of capitalized costs of regulated entities that are expected to be recovered through revenue sources within one year or the normal operating cycle, if longer. Such costs are capitalized if they meet both of the following criteria: a. It is probable that future revenue in an amount at least equal to the capitalized cost will result from inclusion of that cost in allowable costs for rate-making purposes. b. Based on available evidence, the future revenue will be provided to permit recovery of the previously incurred cost rather than to provide for expected levels of similar future costs. If the revenue will be provided through an automatic rate-adjustment clause, this criterion requires that the regulator's intent clearly be to permit recovery of the previously incurred cost.

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Carrying amount as of the balance sheet date of capitalized costs of regulated entities that are not expected to be recovered through revenue sources within one year or the normal operating cycle if longer.

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- Definition

The amount for the individual regulatory liability as itemized in a table of regulatory liabilities as of the end of the period.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 980
-SubTopic 405
-Section 25
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6500807&loc=d3e48068-110394

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The amount for the individual regulatory current liability as itemized in a table of regulatory current liabilities as of the end of the period.

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- Definition

The amount for the individual regulatory noncurrent liability as itemized in a table of regulatory noncurrent liabilities as of the end of the period.

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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 210.5-02.24)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Regulatory Assets and Liabilities (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Nov. 14, 2016
Regulatory Assets and Liabilities
Current regulatory assets	$ 454	$ 536
Non-current regulatory assets	9,728	10,164
Regulatory assets	10,182	10,700
Current regulatory liabilities	173	154
Non-current regulatory liabilities	6	3
Regulatory liabilities	179	157
Bellefonte site contract to sell			$ 111
Net book value and related ARO's of Bellefonte assets	121
Amount received on Bellefonte contract to sell	22
Amount to receive on Bellefonte contract to sell at closing	$ 89
Max number of years buyer had to close	2 years
Yearly amortization of Deferred nuclear generating units		0
Fuel cost adjustment tax equivalents
Regulatory Assets and Liabilities
Current regulatory liabilities	$ 151	148
Unrealized gains/losses on commodity derivatives
Regulatory Assets and Liabilities
Current regulatory liabilities	22	6
Non-current regulatory liabilities	6	3
Deferred nuclear generating units
Regulatory Assets and Liabilities
Current regulatory assets	237	237
Non-current regulatory assets	915	850
Unrealized gains/losses on commodity derivatives
Regulatory Assets and Liabilities
Current regulatory assets	104	122
Non-current regulatory assets	32	56
Fuel cost adjustment receivable/liability
Regulatory Assets and Liabilities
Current regulatory assets	41	98
Environmental agreements
Regulatory Assets and Liabilities
Current regulatory assets	27	34
Non-current regulatory assets	15	18
Environmental cleanup costs - Kingston ash spill
Regulatory Assets and Liabilities
Current regulatory assets	42	42
Non-current regulatory assets	288	299
Other current regulatory assets
Regulatory Assets and Liabilities
Current regulatory assets	3	3
Deferred pension costs and other post-retirement benefits costs
Regulatory Assets and Liabilities
Non-current regulatory assets	5,330	5,385
Unrealized losses on interest rate derivatives
Regulatory Assets and Liabilities
Non-current regulatory assets	1,106	1,547
Nuclear decommissioning costs
Regulatory Assets and Liabilities
Non-current regulatory assets	935	938
Non-nuclear decommissioning costs
Regulatory Assets and Liabilities
Non-current regulatory assets	863	819
Other non-current regulatory assets
Regulatory Assets and Liabilities
Non-current regulatory assets	$ 244	$ 252