Investment in Constellation Energy Nuclear Group, LLC (Tables)

12 Months Ended

Dec. 31, 2014

Business Combinations [Abstract]

Schedule of total equity in earnings of investment in CENG

The following assets and liabilities of CENG were recorded within Generation’s Consolidated Balance Sheets as of the date of integration, adjusted for the modifications discussed above:

Fair Values	Exelon and Generation
Current assets	$	499
Nuclear decommissioning trust fund	1,955
Property, plant and equipment	3,017
Nuclear fuel	482
Other assets	10
Total assets	5,963
Current liabilities	237
Asset retirement obligation	1,760
Pension and other employee benefit obligations	281
Unamortized energy contract liabilities	171
Other liabilities	114
Total liabilities	2,563
Total net assets	$	3,400