Recently Issued Accounting Standards, Not Yet Adopted	9 Months Ended
Recently Issued Accounting Standards, Not Yet Adopted	Sep. 30, 2015
Recently Issued Accounting Standards, Not Yet Adopted	(4) RECENTLY ISSUED ACCOUNTING STANDARDS, NOT YET ADOPTED Revenue from Contracts with Customers (ASC 606) In May 2014, the FASB issued new recognition and disclosure requirements for revenue from contracts with customers, which supersedes the existing revenue recognition guidance. The new recognition requirements focus on when the customer obtains control of the goods or services, rather than the current risks and rewards model of recognition. The core principle of the new standard is that an entity will recognize revenue when it transfers goods or services to its customers in an amount that reflects the consideration an entity expects to be entitled to for those goods or services. The new disclosure requirements will include information intended to communicate the nature, amount, timing and any uncertainty of revenue and cash flows from applicable contracts, including any significant judgments and changes in judgments and assets recognized from the costs to obtain or fulfill a contract. Entities will generally be required to make more estimates and use more judgment under the new standard. The new requirements will be effective for PHI beginning January 1, 2018, and may be implemented either retrospectively for all periods presented, or as a cumulative-effect adjustment as of January 1, 2018. Early adoption is permitted, but not before January 1, 2017. PHI is currently evaluating the potential impact of this new guidance on its consolidated financial statements and which implementation approach to select. Presentation of Debt Issuance Costs (ASC 835) In April 2015, the FASB issued new guidance for the presentation of debt issuance costs on the balance sheet. Debt issuance costs are currently required to be presented on the balance sheet as assets. However, under the new requirements, these debt issuance costs will be offset against the debt to which the costs relate. The new requirements will be effective for PHI beginning January 1, 2016, and are required to be implemented on a retrospective basis for all periods presented. Early adoption is permitted. PHI is currently evaluating the potential impact of this new guidance on its consolidated financial statements, but the impact is not expected to be material. Fair Value Measurement (ASC 820) In May 2015, the FASB issued new disclosure requirements for investment fair values. Under the new requirements, investment fair values based on net asset value per share will continue to be disclosed, however, the investment fair values will no longer be included within the fair value tables and a level will not be assigned to those investment fair values. The new requirements are effective for PHI beginning January 1, 2016, and are required to be implemented on a retrospective basis for all periods presented. Early adoption is permitted. PHI is currently evaluating the potential impact of this new guidance on its consolidated financial statements. Business Combination (ASC 805) In September 2015, the FASB issued new guidance on adjustments to provisional amounts recognized in a business combination, which are currently recognized on a retrospective basis. Under the new requirements, adjustments will be recognized in the reporting period in which the adjustments are determined. The effects of changes in depreciation, amortization, or other income arising from changes to the provisional amounts, if any, are included in earnings of the reporting period in which the adjustments to the provisional amounts are determined. An entity is also required to present separately on the face of the income statement or disclose in the notes the portion of the amount recorded in current-period earnings by line item that would have been recorded in previous reporting periods if the adjustment to the provisional amounts had been recognized as of the acquisition date. The new requirements will be effective for PHI beginning January 1, 2016, and are required to be implemented on a prospective basis. Early adoption is permitted. PHI currently anticipates it may be affected by the new guidance if its Merger with Exelon is consummated.
Potomac Electric Power Co [Member]
Recently Issued Accounting Standards, Not Yet Adopted	(4) RECENTLY ISSUED ACCOUNTING STANDARDS, NOT YET ADOPTED Revenue from Contracts with Customers (ASC 606) In May 2014, the FASB issued new recognition and disclosure requirements for revenue from contracts with customers, which supersedes the existing revenue recognition guidance. The new recognition requirements focus on when the customer obtains control of the goods or services, rather than the current risks and rewards model of recognition. The core principle of the new standard is that an entity will recognize revenue when it transfers goods or services to its customers in an amount that reflects the consideration an entity expects to be entitled to for those goods or services. The new disclosure requirements will include information intended to communicate the nature, amount, timing and any uncertainty of revenue and cash flows from applicable contracts, including any significant judgments and changes in judgments and assets recognized from the costs to obtain or fulfill a contract. Entities will generally be required to make more estimates and use more judgment under the new standard. The new requirements will be effective for Pepco beginning January 1, 2018, and may be implemented either retrospectively for all periods presented, or as a cumulative-effect adjustment as of January 1, 2018. Early adoption is permitted, but not before January 1, 2017. Pepco is currently evaluating the potential impact of this new guidance on its financial statements and which implementation approach to select. Presentation of Debt Issuance Costs (ASC 835) In April 2015, the FASB issued new guidance for the presentation of debt issuance costs on the balance sheet. Debt issuance costs are currently required to be presented on the balance sheet as assets. However, under the new requirements, these debt issuance costs will be offset against the debt to which the costs relate. The new requirements will be effective for Pepco beginning January 1, 2016, and are required to be implemented on a retrospective basis for all periods presented. Early adoption is permitted. Pepco is currently evaluating the potential impact of this new guidance on its financial statements, but the impact is not expected to be material. Business Combination (ASC 805) In September 2015, the FASB issued new guidance on adjustments to provisional amounts recognized in a business combination, which are currently recognized on a retrospective basis. Under the new requirements, adjustments will be recognized in the reporting period in which the adjustments are determined. The effects of changes in depreciation, amortization, or other income arising from changes to the provisional amounts, if any, are included in earnings of the reporting period in which the adjustments to the provisional amounts are determined. An entity is also required to present separately on the face of the income statement or disclose in the notes the portion of the amount recorded in current-period earnings by line item that would have been recorded in previous reporting periods if the adjustment to the provisional amounts had been recognized as of the acquisition date. The new requirements will be effective for Pepco beginning January 1, 2016, and are required to be implemented on a prospective basis. Early adoption is permitted. Pepco currently anticipates it may be affected by the new guidance if its Merger with Exelon is consummated.
Delmarva Power & Light Co/De [Member]
Recently Issued Accounting Standards, Not Yet Adopted	(4) RECENTLY ISSUED ACCOUNTING STANDARDS, NOT YET ADOPTED Revenue from Contracts with Customers (ASC 606) In May 2014, the FASB issued new recognition and disclosure requirements for revenue from contracts with customers, which supersedes the existing revenue recognition guidance. The new recognition requirements focus on when the customer obtains control of the goods or services, rather than the current risks and rewards model of recognition. The core principle of the new standard is that an entity will recognize revenue when it transfers goods or services to its customers in an amount that reflects the consideration an entity expects to be entitled to for those goods or services. The new disclosure requirements will include information intended to communicate the nature, amount, timing and any uncertainty of revenue and cash flows from applicable contracts, including any significant judgments and changes in judgments and assets recognized from the costs to obtain or fulfill a contract. Entities will generally be required to make more estimates and use more judgment under the new standard. The new requirements will be effective for DPL beginning January 1, 2018, and may be implemented either retrospectively for all periods presented, or as a cumulative-effect adjustment as of January 1, 2018. Early adoption is permitted, but not before January 1, 2017. DPL is currently evaluating the potential impact of this new guidance on its financial statements and which implementation approach to select. Presentation of Debt Issuance Costs (ASC 835) In April 2015, the FASB issued new guidance for the presentation of debt issuance costs on the balance sheet. Debt issuance costs are currently required to be presented on the balance sheet as assets. However, under the new requirements, these debt issuance costs will be offset against the debt to which the costs relate. The new requirements will be effective for DPL beginning January 1, 2016, and are required to be implemented on a retrospective basis for all periods presented. Early adoption is permitted. DPL is currently evaluating the potential impact of this new guidance on its financial statements, but the impact is not expected to be material. Business Combination (ASC 805) In September 2015, the FASB issued new guidance on adjustments to provisional amounts recognized in a business combination, which are currently recognized on a retrospective basis. Under the new requirements, adjustments will be recognized in the reporting period in which the adjustments are determined. The effects of changes in depreciation, amortization, or other income arising from changes to the provisional amounts, if any, are included in earnings of the reporting period in which the adjustments to the provisional amounts are determined. An entity is also required to present separately on the face of the income statement or disclose in the notes the portion of the amount recorded in current-period earnings by line item that would have been recorded in previous reporting periods if the adjustment to the provisional amounts had been recognized as of the acquisition date. The new requirements will be effective for DPL beginning January 1, 2016, and are required to be implemented on a prospective basis. Early adoption is permitted. DPL currently anticipates it may be affected by the new guidance if its Merger with Exelon is consummated.
Atlantic City Electric Co [Member]
Recently Issued Accounting Standards, Not Yet Adopted	(4) RECENTLY ISSUED ACCOUNTING STANDARDS, NOT YET ADOPTED Revenue from Contracts with Customers (ASC 606) In May 2014, the FASB issued new recognition and disclosure requirements for revenue from contracts with customers, which supersedes the existing revenue recognition guidance. The new recognition requirements focus on when the customer obtains control of the goods or services, rather than the current risks and rewards model of recognition. The core principle of the new standard is that an entity will recognize revenue when it transfers goods or services to its customers in an amount that reflects the consideration an entity expects to be entitled to for those goods or services. The new disclosure requirements will include information intended to communicate the nature, amount, timing and any uncertainty of revenue and cash flows from applicable contracts, including any significant judgments and changes in judgments and assets recognized from the costs to obtain or fulfill a contract. Entities will generally be required to make more estimates and use more judgment under the new standard. The new requirements will be effective for ACE beginning January 1, 2018, and may be implemented either retrospectively for all periods presented, or as a cumulative-effect adjustment as of January 1, 2018. Early adoption is permitted, but not before January 1, 2017. ACE is currently evaluating the potential impact of this new guidance on its consolidated financial statements and which implementation approach to select. Presentation of Debt Issuance Costs (ASC 835) In April 2015, the FASB issued new guidance for the presentation of debt issuance costs on the balance sheet. Debt issuance costs are currently required to be presented on the balance sheet as assets. However, under the new requirements, these debt issuance costs will be offset against the debt to which the costs relate. The new requirements will be effective for ACE beginning January 1, 2016, and are required to be implemented on a retrospective basis for all periods presented. Early adoption is permitted. ACE is currently evaluating the potential impact of this new guidance on its consolidated financial statements, but the impact is not expected to be material. Business Combination (ASC 805) In September 2015, the FASB issued new guidance on adjustments to provisional amounts recognized in a business combination, which are currently recognized on a retrospective basis. Under the new requirements, adjustments will be recognized in the reporting period in which the adjustments are determined. The effects of changes in depreciation, amortization, or other income arising from changes to the provisional amounts, if any, are included in earnings of the reporting period in which the adjustments to the provisional amounts are determined. An entity is also required to present separately on the face of the income statement or disclose in the notes the portion of the amount recorded in current-period earnings by line item that would have been recorded in previous reporting periods if the adjustment to the provisional amounts had been recognized as of the acquisition date. The new requirements will be effective for ACE beginning January 1, 2016, and are required to be implemented on a prospective basis. Early adoption is permitted. ACE currently anticipates it may be affected by the new guidance if its Merger with Exelon is consummated.