The portion of the acquisition settlement related to the expected cost of developing new generation.

No definition available.

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- Definition

Power Volume

+ References

No definition available.

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- Definition

Development costs incurred, including capitalized costs and costs charged to expense, in oil and gas activities.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 235
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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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Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

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- Definition

Sum of the carrying amounts as of the balance sheet date of all investments.

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- Definition

Amount of lease operating expense related to property used in oil and gas production.

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- Definition

Amount of expense (income) related to the increase (decrease) in reserve for business combination costs. Includes, but is not limited to, legal, accounting, and other costs incurred to consummate the merger.

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- Definition

Amount of net occupancy expense that may include items, such as depreciation of facilities and equipment, lease expenses, property taxes and property and casualty insurance expense.

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-Publisher FASB
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- Definition

Generally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services. Includes selling, general and administrative expense.

+ References

No definition available.

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- Definition

Costs that are essential to acquiring the lease and would not otherwise have been incurred without the lease agreement, including evaluating the lessee's credit condition, guarantees, and collateral and costs incurred negotiating, processing, and closing the lease agreement.

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Commitments and Contingencies - Commitments Narrative (Details) $ in Millions	1 Months Ended		3 Months Ended
	Nov. 30, 2015 USD ($)	Sep. 23, 2015 USD ($)	Mar. 31, 2017 USD ($) MW	Dec. 31, 2016 USD ($)	Mar. 31, 2016 USD ($)	Jun. 30, 2014 USD ($)
Guarantor Obligations [Line Items]
Guarantor Obligations, Maximum Exposure, Undiscounted			$ 48
Noncash Merger Related Costs					$ 503
Power Volume \| MW			220
Exelon Generation Co L L C [Member]
Guarantor Obligations [Line Items]
Noncash Merger Related Costs					3
Costs Incurred, Development Costs			$ 456
Commonwealth Edison Co [Member]
Guarantor Obligations [Line Items]
Noncash Merger Related Costs					0
PECO Energy Co [Member]
Guarantor Obligations [Line Items]
Noncash Merger Related Costs					0
Baltimore Gas and Electric Company [Member]
Guarantor Obligations [Line Items]
Oil and Gas Property, Lease Operating Expense				$ 29
Occupancy, Net	$ 42	$ 12
Noncash Merger Related Costs					$ 0
Operating Leases, Income Statement, Initial Direct Costs				25
Operating Expenses				$ 28
Minimum [Member] \| Exelon Generation Co L L C [Member]
Guarantor Obligations [Line Items]
Business Acquisition, Development Of New Generation Cost			450
Maximum [Member] \| Exelon Generation Co L L C [Member]
Guarantor Obligations [Line Items]
Business Acquisition, Development Of New Generation Cost			$ 550
Merger Commitment [Member]
Guarantor Obligations [Line Items]
Investments						$ 1,000
Merger Commitment [Member] \| Minimum [Member]
Guarantor Obligations [Line Items]
Investments						0
Merger Commitment [Member] \| Maximum [Member]
Guarantor Obligations [Line Items]
Investments						$ 0