Common Stock, Contingent Shares Required to be Issued in Agreement

No definition available.

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- Details

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- Definition

Shares of common stock reserved for conversion of outstanding warrants.

+ References

No definition available.

+ Details

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- Definition

Fair value of settled performance share awards.

+ References

No definition available.

+ Details

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- Definition

Fair value of settled restricted stock

+ References

No definition available.

+ Details

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- Definition

Number of warrants outstanding. Equity warrants represents derivative securities that give the holder the right to purchase securities (usually equity) from the issuer at a specific price within a certain time frame. Warrants are often included in a new debt issue to entice investors by a higher return potential.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Obligations related to outstanding performance share awards that will be settled in cash

+ References

No definition available.

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

Weighted average grant date fair value of performance share awards.

+ References

No definition available.

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

Obligations related to outstanding restricted stock units not yet settled

+ References

No definition available.

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- Definition

Obligations related to outstanding restricted stock units that will be settled in cash

+ References

No definition available.

+ Details

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- Definition

Share-based Compensation by Share-based Payment Award, Percentage of Awards to be Settled in Cash

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Share-based Compensation by Share-based Payment Award, Percentage of Awards to be Settled in Cash if Agreement Conditions are Met

+ References

No definition available.

+ Details

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- Definition

Share-based Compensation by Share-based Payment Award, Percentage of Awards to be Settled in Stock

+ References

No definition available.

+ Details

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- Definition

Share-based Compensation by Share-based Payment Award, Performance Period

+ References

No definition available.

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- Definition

Share-based Compensation by Share-based Payment Award, Target Award Mix

+ References

No definition available.

+ Details

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- Definition

Weighted Average Period Non Vested Performance Share Awards Are Expected To Be Recognized Over

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (i)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

+ References

No definition available.

+ Details

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- Definition

Unrecognized cost of unvested options awarded to employees as compensation.

+ References

No definition available.

+ Details

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- Definition

The number of issuer's shares to which the forward contract is indexed.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 40

-Section 50

-Paragraph 5

-Subparagraph (a)(3)

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- Definition

Current fair value of each cash settlement alternative for each freestanding forward contract.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 40

-Section 50

-Paragraph 5

-Subparagraph (d)

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- Definition

Fees and commissions from underwriting securities, private placements of securities, investment advisory and management services, merger and acquisition services, and other related consulting fees. Include fees and commissions from securities brokerage activities, from the sale and servicing of mutual funds, from the purchase and sale of securities and money market instruments where the bank is acting as agent for other banks or customers, and from the lending of securities owned by the bank or by bank customers (exclusive of trading revenue). Also includes the bank's proportionate share of the income or loss before extraordinary items and other adjustments from its investments in: unconsolidated subsidiaries, associated companies and corporate joint ventures, unincorporated joint ventures, general partnerships, and limited partnerships over which the bank exercises significant influence and that are principally engaged in investment banking, advisory, brokerage, or securities underwriting activities.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-04.13(b))

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 13

-Subparagraph b

-Article 9

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- Definition

Carrying value as of the balance sheet date of long-term debt (with maturities initially due after one year or beyond the operating cycle if longer) identified as Junior Subordinated Notes, which have a lower priority than senior instruments, excluding current portion.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22)

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- Definition

Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)(iii)(1)

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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-Name Accounting Standards Codification

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-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(2)

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(3)

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- Definition

Amount per share or per unit of equity securities issued by non-development stage entity.

+ References

No definition available.

+ Details

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- Definition

The number of securities classified as temporary equity that have been allocated to investors to buy. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. If convertible, the issuer does not control the actions or events necessary to issue the maximum number of shares that could be required to be delivered under the conversion option if the holder exercises the option to convert the stock to another class of equity. If the security is a warrant or a rights issue, the warrant or rights issue is considered to be temporary equity if the issuer cannot demonstrate that it would be able to deliver upon the exercise of the option by the holder in all cases. Includes stock with put option held by ESOP and stock redeemable by holder only in the event of a change in control of the issuer.

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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 210.5-02.27(b))

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 28

-Subparagraph b

-Article 5

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- Definition

Number of shares held for each class of treasury stock.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 30

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655

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- Definition

The amount allocated to treasury stock. Treasury stock is common and preferred shares of an entity that were issued, repurchased by the entity, and are held in its treasury.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 30

-Section 50

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=6405834&loc=d3e23315-112656

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Common Stock - Narrative (Details) (USD $)	1 Months Ended	3 Months Ended	12 Months Ended
Common Stock - Narrative (Details) (USD $)	Jun. 30, 2014	Jun. 30, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Common Stock Narrative Information [Line Items]
Common stock shares reserved for warrant conversion			24,511
Equity offering	57,500,000.0	57,500,000.0
Price per share (in usd per share)	$ 35us-gaap_SharesIssuedPricePerShare	$ 35us-gaap_SharesIssuedPricePerShare
Underwriting discount	$ 60,000,000	$ 35,000,000
Shares required to settle agreement			4,000,000
Junior subordinated notes	1,150,000,000us-gaap_JuniorSubordinatedLongTermNotes	1,150,000,000us-gaap_JuniorSubordinatedLongTermNotes
Shares of junior subordinated notes	23,000,000	23,000,000
Treasury stock, at cost			2,327,000,000us-gaap_TreasuryStockValue	2,327,000,000us-gaap_TreasuryStockValue
Expiration period			10 years
Obligations of outstanding restricted stock not settled			85,000,000	77,000,000
Settlement of restricted stock			43,000,000	28,000,000	25,000,000
Unrecognized compensation costs of nonvested restricted stock			59,000,000
Weighted average grant date fair value of performance shares (in usd per share)			28.75	31.55	39.71
Settlement of performance shares			27,000,000	26,000,000	23,000,000
Settlement of performance shares in cash			13,000,000	12,000,000	3,000,000
Unrecognized compensation costs of performance based shares			54,000,000
Weighted-average period of recognition of unrecognized compensation costs of performance based shares			1 year 7 months 6 days
2004 Repurchase Plan [Member]
Common Stock Narrative Information [Line Items]
Common stock held as treasury stock			35,000,000
Treasury stock, at cost			2,300,000,000
Commonwealth Edison Co [Member]
Common Stock Narrative Information [Line Items]
Warrants outstanding			73,533	73,709
Common stock shares reserved for warrant conversion				24,570
Performance Shares [Member]
Common Stock Narrative Information [Line Items]
Mix of awards				67.00%
Percentage to be settled as common stock			50.00%
Percentage to be settled as cash			50.00%
Percentage to be settled as cash if ownership requirements are met			100.00%
Weighted average grant date fair value (in usd per share)			$ 28.75
Nonvested Stock Option [Member]
Common Stock Narrative Information [Line Items]
Unrecognized compensation costs			1,000,000
Weighted-average period of recognition of unrecognized compensation costs			1 year
Employee Stock Option [Member]
Common Stock Narrative Information [Line Items]
Requisite service period			4 years
Restricted Stock [Member]
Common Stock Narrative Information [Line Items]
Mix of awards				33.00%
Weighted-average period of recognition of unrecognized compensation costs			2 years 1 month 6 days
Weighted average grant date fair value (in usd per share)			$ 28.71	$ 31.06	$ 39.94
Minimum [Member]
Common Stock Narrative Information [Line Items]
Net proceeds at the forward price specified in agreements	1,800,000,000	1,800,000,000
Minimum [Member] \| Restricted Stock [Member]
Common Stock Narrative Information [Line Items]
Requisite service period			3 years
Maximum [Member]
Common Stock Narrative Information [Line Items]
Net proceeds at the forward price specified in agreements	$ 1,900,000,000	$ 1,900,000,000
Maximum [Member] \| Restricted Stock [Member]
Common Stock Narrative Information [Line Items]
Requisite service period			5 years
LTIP [Member]
Common Stock Narrative Information [Line Items]
Shares authorized			16,000,000
2013 Plan [Member] \| Performance Shares [Member]
Common Stock Narrative Information [Line Items]
Vesting period				3 years
2012 Plan [Member] \| Performance Shares [Member]
Common Stock Narrative Information [Line Items]
Vesting period				3 years
Performance period				1 year
Performance Share Transition Award [Member]
Common Stock Narrative Information [Line Items]
Percentage to be settled as common stock				50.00%
Percentage to be settled as cash				50.00%
Percentage to be settled as cash if ownership requirements are met				100.00%
Performance Share Transition Award [Member] \| Performance Shares [Member]
Common Stock Narrative Information [Line Items]
Vesting period				1 year
Performance period				2 years