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Subsequent Events Subsequent Events - Narrative (Details) - Exelon Generation Co L L C [Member] - Subsequent Event [Member] $ in Millions | Dec. 31, 2018 USD ($)
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Subsequent Event [Line Items] |
Net long-lived assets | $ 750
Non-recourse debt | 510
Antelope Valley [Member] |
Subsequent Event [Line Items] |
Net long-lived assets | 1,990
Antelope Valley [Member] | ExGenRenewablesIVNov2024 [Member] |
Subsequent Event [Line Items] |
Non-recourse debt | $ 830

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- Definition Amount of net assets (liabilities). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 946 -SubTopic 225 -Section S99 -Paragraph 3 -Subparagraph (SX 210.6-09(6)) -URI http://asc.fasb.org/extlink&oid=6488393&loc=d3e606914-122999 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 946 -SubTopic 210 -Section S99 -Paragraph 2 -Subparagraph (SX 210.6-05(4)) -URI http://asc.fasb.org/extlink&oid=6488278&loc=d3e604008-122996 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 946 -SubTopic 205 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=79984436&loc=d3e9915-115836 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 30 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=77885760&loc=SL35686385-199418 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 946 -SubTopic 225 -Section S99 -Paragraph 3 -Subparagraph (SX 210.6-09(7)) -URI http://asc.fasb.org/extlink&oid=6488393&loc=d3e606914-122999 + Details
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- Definition Amount of debt for which creditor does not have general recourse to the debtor but rather has recourse only to the property used for collateral in the transaction or other specific property. + References No definition available. + Details
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Balance Type: | credit
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- Definition Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event. + References No definition available. + Details
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Namespace Prefix: | us-gaap_
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Balance Type: | na
Period Type: | duration

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- Details
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Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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- Details
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Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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- Details
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Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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- Details
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Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |