New Accounting Pronouncements (Exelon, Generation, ComEd and PECO)	6 Months Ended
Jun. 30, 2011
New Accounting Pronouncements And Changes In Accounting Principles Abstract
Schedule Of New Accounting Pronouncements And Changes In Accounting Principles [Text Block]	2. New Accounting Pronouncements (Exelon, Generation, ComEd and PECO) There were no recently issued accounting standards adopted by the Registrants during the period. The following recently issued accounting standards are not yet required to be reflected in the combined consolidated financial statements of the Registrants: Fair Value Measurements In May 2011, the FASB issued authoritative guidance amending existing guidance for measuring fair value and for disclosing information about fair value measurements. The FASB indicated that it generally does not intend the amendments to result in a change to current accounting. Required disclosures are expanded under the new guidance, especially for fair value measurements that are categorized within Level 3 of the fair value hierarchy, for which quantitative information about the unobservable inputs, the valuation processes used by the entity, and the sensitivity of the measurement to the unobservable inputs will be required. Entities will also be required to disclose the categorization by level of the fair value hierarchy for items that are not measured at fair value in the statement of financial position but for which the fair value is required to be disclosed. The Registrants are currently assessing the effects this guidance may have on their consolidated financial statements. The guidance is effective for the Registrants for periods beginning after December 15, 2011 and is required to be applied prospectively. Presentation of Comprehensive Income In June 2011, the FASB issued authoritative guidance requiring an entity to present net income and other comprehensive income in a single continuous statement of comprehensive income or in two separate, but consecutive, statements. The new guidance does not change the components that are recognized in net income and the components that are recognized in other comprehensive income. Each of the Registrants currently presents a single statement of comprehensive income and, therefore, the adoption of this guidance will not affect the Registrants' financial statements. This guidance is effective for the Registrants for periods beginning after December 15, 2011 and is required to be applied retroactively.

New Accounting Pronouncements (Exelon, Generation, ComEd and PECO)

6 Months Ended

Jun. 30, 2011

New Accounting Pronouncements And Changes In Accounting Principles Abstract

Schedule Of New Accounting Pronouncements And Changes In Accounting Principles [Text Block]

2. New Accounting Pronouncements (Exelon, Generation, ComEd and PECO)

There were no recently issued accounting standards adopted by the Registrants during the period.

The following recently issued accounting standards are not yet required to be reflected in the combined consolidated financial statements of the Registrants:

Fair Value Measurements

In May 2011, the FASB issued authoritative guidance amending existing guidance for measuring fair value and for disclosing information about fair value measurements. The FASB indicated that it generally does not intend the amendments to result in a change to current accounting. Required disclosures are expanded under the new guidance, especially for fair value measurements that are categorized within Level 3 of the fair value hierarchy, for which quantitative information about the unobservable inputs, the valuation processes used by the entity, and the sensitivity of the measurement to the unobservable inputs will be required. Entities will also be required to disclose the categorization by level of the fair value hierarchy for items that are not measured at fair value in the statement of financial position but for which the fair value is required to be disclosed. The Registrants are currently assessing the effects this guidance may have on their consolidated financial statements. The guidance is effective for the Registrants for periods beginning after December 15, 2011 and is required to be applied prospectively.

Presentation of Comprehensive Income

In June 2011, the FASB issued authoritative guidance requiring an entity to present net income and other comprehensive income in a single continuous statement of comprehensive income or in two separate, but consecutive, statements. The new guidance does not change the components that are recognized in net income and the components that are recognized in other comprehensive income. Each of the Registrants currently presents a single statement of comprehensive income and, therefore, the adoption of this guidance will not affect the Registrants' financial statements. This guidance is effective for the Registrants for periods beginning after December 15, 2011 and is required to be applied retroactively.